My grandmother Adele loved culture and was generous with its gifts. When I was a child, she took me to museums, restaurants, dances. She showered me with gifts from her travels around the world. But I can only remember her giving me one book—a book that, to this day, I have not read. She presented me with her own favorite childhood book: Hans Brinker. My grandmother was happy to share this book with me. She even decorated the title page with her proud writing.
I tried to read it. I adored reading, and would dive into a new pile of books from the library all at once. But something about Hans Brinker just wouldn’t let me in. The story was set in Holland, a long time ago. It felt dull and unfamiliar—even though I was a fan of classics of other times and places. I simply read the first pages over and over. I could not progress.
Standing on a bookshelf in our living room, the book was like something I avoided. It scolded me for not being interested, for not trying hard enough, for disappointing my grandmother.
The book started to fit in, almost forgotten, until Adele asked. Had I read it? Did I like it? Always determined, she wanted to know the answer. I would make some kind of excuse, feel bad, and open it again, hoping for a new reaction. The book weighed on me.
Years passed and finally Adele and I both accepted that I would never read Hans Brinker. Eventually I cleared the book from the shelf. The Hans Brinker experience led me to set a rule that I’ve lived by ever since: Do not ask about a book given as a gift. Don’t ask, despite your desire to discuss it to grow closer. The desire for such connection is what gives book-giving with special meaning—and increases the owner’s possibility to be a letdown.
Guilt is basically the same as for all gifts, though. If the giver doesn’t have the pleasure of seeing or hearing about the gift being enjoyed, and asks whether it is, then the owner—unless she can truthfully say “yes”—either has to admit to not liking the present, or else lie on the spot. Neither is pleasant. So, don’t ask.
1.When the author was a kid, his grandmother ________.
A. took him to travel around the world a lot
B. loved to take him to museums and stores
C. shared her childhood stories with him
D. gave him many gifts
2.What does the author think about the book his grandmother gave him?
A. Boring. B. Interesting.
C. Puzzling. D. Disappointing.
3.The underlined sentence “The book weighed on me” in Paragraph 4 probably means _______.
A. the book is too heavy for the author to carry
B. the author feels stressful facing the book
C. the book is full of powerful viewpoints
D. the author keeps reading the book
4.The author learns from the Hans Brinker’s experience that never________.
A. give others books as gifts
B. lie to people who give you gifts
C. get close to others through gifts
D. talk about the books given as gifts
高三英语阅读理解中等难度题
My grandmother Adele loved culture and was generous with its gifts. When I was a child, she took me to museums, restaurants, dances. She showered me with gifts from her travels around the world. But I can only remember her giving me one book—a book that, to this day, I have not read. She presented me with her own favorite childhood book: Hans Brinker. My grandmother was happy to share this book with me. She even decorated the title page with her proud writing.
I tried to read it. I adored reading, and would dive into a new pile of books from the library all at once. But something about Hans Brinker just wouldn’t let me in. The story was set in Holland, a long time ago. It felt dull and unfamiliar—even though I was a fan of classics of other times and places. I simply read the first pages over and over. I could not progress.
Standing on a bookshelf in our living room, the book was like something I avoided. It scolded me for not being interested, for not trying hard enough, for disappointing my grandmother.
The book started to fit in, almost forgotten, until Adele asked. Had I read it? Did I like it? Always determined, she wanted to know the answer. I would make some kind of excuse, feel bad, and open it again, hoping for a new reaction. The book weighed on me.
Years passed and finally Adele and I both accepted that I would never read Hans Brinker. Eventually I cleared the book from the shelf. The Hans Brinker experience led me to set a rule that I’ve lived by ever since: Do not ask about a book given as a gift. Don’t ask, despite your desire to discuss it to grow closer. The desire for such connection is what gives book-giving with special meaning—and increases the owner’s possibility to be a letdown.
Guilt is basically the same as for all gifts, though. If the giver doesn’t have the pleasure of seeing or hearing about the gift being enjoyed, and asks whether it is, then the owner—unless she can truthfully say “yes”—either has to admit to not liking the present, or else lie on the spot. Neither is pleasant. So, don’t ask.
1.When the author was a kid, his grandmother ________.
A. took him to travel around the world a lot
B. loved to take him to museums and stores
C. shared her childhood stories with him
D. gave him many gifts
2.What does the author think about the book his grandmother gave him?
A. Boring. B. Interesting.
C. Puzzling. D. Disappointing.
3.The underlined sentence “The book weighed on me” in Paragraph 4 probably means _______.
A. the book is too heavy for the author to carry
B. the author feels stressful facing the book
C. the book is full of powerful viewpoints
D. the author keeps reading the book
4.The author learns from the Hans Brinker’s experience that never________.
A. give others books as gifts
B. lie to people who give you gifts
C. get close to others through gifts
D. talk about the books given as gifts
高三英语阅读理解中等难度题查看答案及解析
My grandmother Adele loved culture and was generous with its gifts. When I was a child, she took me to museums, restaurants, dances. She showered me with gifts from her travels around the world. But I can only remember her giving me one book—a book that, to this day, I have not read. She presented me with her own favorite childhood book: Hans Brinker. My grandmother was happy to share this book with me. She even decorated the title page with her proud writing.
I tried to read it. I adored reading, and would dive into a new pile of books from the library all at once. But something about Hans Brinker just wouldn’t let me in. The story was set in Holland, a long time ago. It felt dull and unfamiliar—even though I was a fan of classics of other times and places. I simply read the first pages over and over. I could not progress.
Standing on a bookshelf in our living room, the book was like something I avoided. It scolded me for not being interested, for not trying hard enough, for disappointing my grandmother.
The book started to fit in, almost forgotten, until Adele asked. Had I read it? Did I like it? Always determined, she wanted to know the answer. I would make some kind of excuse, feel bad, and open it again, hoping for a new reaction. The book weighed on me.
Years passed and finally Adele and I both accepted that I would never read Hans Brinker. Eventually I cleared the book from the shelf. The Hans Brinker experience led me to set a rule that I’ve lived by ever since: Do not ask about a book given as a gift. Don’t ask, despite your desire to discuss it to grow closer. The desire for such connection is what gives book-giving with special meaning—and increases the owner’s possibility to be a letdown.
Guilt is basically the same as for all gifts, though. If the giver doesn’t have the pleasure of seeing or hearing about the gift being enjoyed, and asks whether it is, then the owner—unless she can truthfully say “yes”—either has to admit to not liking the present, or else lie on the spot. Neither is pleasant. So, don’t ask.
1. When the author was a kid, his grandmother ________.
took him to travel around the world a lot
loved to take him to museums and stores
shared her childhood stories with him
gave him many gifts
2.What does the author think about the book his grandmother gave him?
A. Boring. B. Interesting. C. Puzzling. D. Disappointing.
3.The underlined sentence “The book weighed on me” in Paragraph 4 probably means _______.
A. the book is too heavy for the author to carry
B. the author feels stressful facing the book
C. the book is full of powerful viewpoints
D. the author keeps reading the book
4.. The author learns from the Hans Brinker’s experience that never________.
A. give others books as gifts
B. lie to people who give you gifts
C. get close to others through gifts
D. talk about the books given as gifts
高三英语阅读理解中等难度题查看答案及解析
It was hot and yet, such a beautiful day. My parents and I picked up my grandmother from the nursing home. We used to go there regularly but the last time I visited my grandmother, she seemed to forget where she was and how to breathe on the massage (按摩) table—it scared me so I thought perhaps it was better to transfer her to a clinic that day.
She had been getting weaker and having aches from sitting in a wheel chair all day, so I called Wang Tao who runs a Chinese massage clinic with his wife and daughter out of their home and told him my concerns wasn't even sure whether my grandmother would be strong enough to get up the stairs or get onto the table.
''We can help her make it'', Wang Tao said. And, we did. Sure there were struggles and funny moments. For example, my grandmother wondered who was the man working on her back, Wang Tao had massaged her over the years at least 20 times. They used to laugh and talk together in Chinese but my grandmother didn't remember. Wang Tao was shocked that my grandmother seemed to have forgotten he is a Chinese man, but he still patiently tried to refresh her memory.
My grandmother was born in California, but her parents who were born in China only spoke Chinese, so Chinese was her first language but English is spoken all around her. Still, our family all felt grateful and happy to hear my grandmother start talking to Wang Tao in Chinese again. It was like the dust just needed clearing. We all laughed a happy laugh. When the session was over, my grandmother took Wang Tao's hand and thanked him for helping her. We ended our day with a Chinese dinner of course-one that ended with my grandmother saying to the massager: please come here and I have to shake your hand. ''Thank you for what you have done. '' she said joyfully as she held this stranger's hand. And then she turned to me, ''Thank you, my grandson. ''
1.What did the author do shortly after visiting his grandmother last time?
A.He had a French dinner with his grandmother.
B.He massaged his grandmother at home by himself.
C.He took his grandmother out of the nursing home.
D.He helped his grandmother transfer to another nursing home.
2.What made Wang Tao surprised at the author's grandmother?
A.Her fluent Chinese.
B.Her failure to recognize him.
C.Her losing the ability of language.
D.Her aches from sitting in a wheel chair.
3.Why did the author feel thankful?
A.His grandmother finally recognized the massager.
B.Wang Tao agreed to have dinner with his family.
C.His grandmother her remembered saying thanks to the massager.
D.Wang Tao made his grandmother begin speaking Chinese again.
4.What does the text mainly show?
A.Grandma's love for children and friend.
B.Friendship and sympathy from strangers.
C.The forgetfulness and helplessness of the old.
D.Family ties and the kindness between people.
高三英语阅读理解中等难度题查看答案及解析
I love my very close friend1.is very generous,kind,loving,caring,and2.(help).She is always helping out people3.need.Her profession is a lawyer,but she is very kind-hearted and very modest as a person.
Every year on her birthday she visits an orphanage(孤儿院)and gifts the little4.(one) with some toys,some eatables,or sometimes what they are in short of.
This birthday she made a5.(decide) to share her kind act with her friends in their circle meeting.Her friends all decided to celebrate their birthdays in the orphanage and gift6.children there with various7.(cookie)!So now,on every member’s birthday they come together to spread joy and love to those children who8.(desperate) want someone to love them.
There are almost 380 children in house.My friend does every bit she can9.(aid) the needy.Maybe we could also promise to celebrate our birthdays with orphaned children.We could love them and more smiles would10. (bring) to their faces.Anyone cares to join us?
高三英语短文填空中等难度题查看答案及解析
It was a lovely day at the park and Stella Bianchi was enjoying the sunshine with her two children when a young boy, aged about four, approached her two-year-old son and pushed him to the ground.
“I’d watched him for a little while and my son was the fourth or fifth child he’d pushed,” she says. “I went over to them, picked up my son, turned to the boy and said, firmly, ‘No, we don’t push.’” What happened next was unexpected.
“The boy’s mother ran toward me from across the park,” Stella says, “I thought she was coming over to apologize, but instead she started shouting at me for blaming her child. All I did was let him know his behavior was unacceptable. Was I supposed to sit back while her kid did whatever he wanted and hurt other children?”
Getting your own children to play nice is difficult enough. Dealing with other people’s children has become a hidden danger.
In my house, jumping on the sofa is not allowed. In my sister’s house it’s encouraged. I find myself saying “no” a lot when her kids are over at mine. That’s OK between sisters but becomes dangerous when you’re talking to the children of friends or acquaintances.
“Kids aren’t all raised the same,” agrees Professor Naomi White of Monash University.” But there is still an idea that they’re the property of the parent. We see our children as a mirror of ourselves, so if you’re saying that my child is behaving improperly, then that’s somehow a criticism(批评) of me.”
In those situations, it’s difficult to know whether to approach the child directly or the parent first. There are two opinions.
“I’d go to the child first,” says Andrew Fuller, author of Tricky Kids. “Usually a quiet reminder that ‘we don’t do that here’ is enough. Kids have antennae (直觉) for how to behave in different settings.”
He points out bringing it up with the parent first may make them feel careless, which could cause problems. Of course, approaching the child first can bring its own headaches, too.
This is why White recommends that you approach the parents first. Raise your concerns with the parents and ask them to deal with it,” she says.
Asked how to approach a parent in this situation, psychologist Meredith Fuller answers: “Explain your needs as well as stressing the importance of the friendship. Start with something like: ‘I know you’ll think I’m silly but in my house I don’t want…’”
1.What did Stella Bianchi expect the young boy’s mother to do when she talked to him?
A. Make an apology B. Come over to stop her
C. Blame her own boy D. Take her own boy away
2.What does the author say about dealing with other people’s children?
A. It’s important not to hurt them in any way
B. It’s no use trying to stop their wrongdoing
C. It’s advisable to treat them as one’s own kids
D. It’s possible for one to get into lots of trouble
3.According to professor Naomi White, when one’s kids are criticized, their parents will probably feel ______.
A. discouraged B. hurt C. puzzled D. affected
4. What should one do when seeing other people’s kids misbehave according to Andrew Fuller?
A. Talk to them directly in a mild way B. Complain to their parents politely
C. Simply leave them alone D. Punish them lightly
高三英语阅读理解中等难度题查看答案及解析
I fell in love with Yosemite National Park the first time I saw it, when I was 13.My parents took us there for camping. On the way out, I asked them to wait while I ran up to El Capitan, a rock of 3,300 feet straight up. I touched that giant rock and knew I wanted to climb it. That has been my life’s passion (钟爱) ever since— the rocks and mountains of Yosemite. I’ve long made Yosemite my .
About 15 years ago I started seeing a lot of ,like toilet paper, beer cans, and empty boxes, around the area. It’s me why visitors started respecting the place and treated such a beautiful home-like place this way.
I tried trash (垃圾) myself, but the job was too big. I would an hour or two on the job, only to find the area trashed all over again weeks later. Finally, I got so it that I decided something had to change.
As a rock-climbing guide, I knew about organizing any big event. But in 2004,together with some climbers, I set a date for a .On that day, more than 300 people .Over three days we collected about 6,000 pounds of trash. It was amazing how much we were able to .I couldn’t believe the we made—the park looked clean!
Each year volunteers come for the cleanup from everywhere. In 2007 alone,2,945 people picked up 42,330 pounds of trash and 132 miles of roadway.
I often hear people about their surroundings. If you are one of them, I would say the only way to change things is by rather than complaining. We need to teach by .You can’t blame others you start with yourself.
1.A. distant B. huge C. narrow D. loose
2.A. immediately B. finally C. gradually D. recently
3.A.imagining B. painting C. describing D. climbing
4.A. garden B. home C. lab D. palace
5.A .material B. resources C. waste D. goods
6.A. beyond B. against C. over D. within
7.A. more B. most C. less D. least
8.A. throwing away B. picking up C. breaking down D. digging out
9.A. kill B. save C. wait D. spend
10.A. satisfied with B. delighted in C. tired of D. used to
11.A.something B. anything C. everything D. nothing
12.A. cleanup B. party C. picnic D. concert
13.A. dropped out B. showed up C. looked around D. called back
14.A. demand B. receive C. accomplish D. overcome
15.A .plan B. visit C. contact D. difference
16.A. crossed B. measured C. covered D. designed
17.A.talk B. complain C. argue D. quarrel
18.A. doing B. thinking C. questioning D. watching
19.A.method B. explanation C. example D. research
20.A. although B. if C. when D. unless
高三英语完形填空中等难度题查看答案及解析
I fell in love with Yosemite National Park the first time I saw it, when I was 13. My parents took us there for camping. On the way out, I asked them to wait while I ran up to E1 Capitan, a _________ rock of 3,300 feet straight up. I touched that giant rock and knew _________ I wanted to climb it. That has been my life’s passion (钟爱) ever since--_________ the rocks and mountains of Yosemite. I’ve long made Yosemite my _________.
About 15 years ago I started seeing a lot of _________, like toilet paper, beer cans, and empty boxes, around the area. It’s _________ me why visitors started respecting the place less and treated such a _________ home-like place this way.
I tried _________ trash(垃圾)myself, but the job was too big. I would _________an hour or two on the job, only to find the area trashed all over again weeks later. Finally, I got so ____________ it that I decided something had to ______________.
As a rock-climbing guide, I knew ______________about organizing any big event. But in 2004, together with some climbers, I set a date for a ______________. On that day, more than 300 people ______________. Over three days we collected about 6,000 pounds of trash. It was ______________how much we were able to accomplish. I couldn’t believe the ______________ we made --the park looked clean!
Each year volunteers come for the cleanup from everywhere. In 2007 alone, 2,945 people picked up 42,330 pounds of trash and ______________ 132 miles of roadway.
I often hear people ______________ about their surroundings. If you are one of them, I would say the only way to change things is by ______________ rather than complaining. We need to teach by ______________. You can’t blame others unless you start with yourself.
1.A.distant B.hard C.loose D.huge
2.A.gradually B.finally C.immediately D.recently
3.A.climbing B.painting C.measuring D.approaching
4.A.home B.palace C.garden D.shelter
5.A.dust B.waste C.materials D.resources
6.A.against B.over C.beyond D.within
7.A.new B.safe C.happy D.beautiful
8.A.throwing away B.breaking down C.picking up D.digging out
9.A.wait B.save C.kill D.spend
10.A.delighted in B.tired of C.satisfied with D.used to
11.A.aim B.stress C.depend D.change
12.A.anything B.nothing C.everything D.something
13.A.cleanup B.picnic C.party D.concert
14.A.looked around B.called back C.dropped out D.showed up
15.A.puzzling B.amazing C.amusing D.interesting
16.A.plan B.visit C.difference D.contact
17.A.covered B.crossed C.measured D.designed
18.A.argue B.complain C.quarrel D.talk
19.A.thinking B.questioning C.doing D.watching
20.A.method B.explanation C.research D.example
高三英语完形填空中等难度题查看答案及解析
I fell in love with Yosemite National Park the first time I saw it, when I was 13. My parents took us there for camping. On the way out, I asked them to wait while I ran up to El Capitan, a __ __ rock of 3,300 feet straight up. I touched that giant rock and knew __ __ I wanted to climb it. That has been my life's passion (钟爱) ever since — __ __ the rocks and mountains of Yosemite. I've long made Yosemite my __ __.
About 15 years ago I started seeing a lot of __ __, like toilet paper, beer cans, and empty boxes, around the area. It's __ __ me why visitors started respecting the place __ __ and treated such a beautiful homelike place this way.
I tried __ __ trash (垃圾) myself, but the job was too big. I would __ __ an hour or two on the job, only to find the area trashed all over again weeks later. Finally, I got so __ __ it that I decided something had to change.
As a rockclimbing guide, I knew __ __ about organizing any big event. But in 2004,together with some climbers, I set a date for a __ __. On that day,more than 300 people __ __. Over three days we collected about 6,000 pounds of trash. It was amazing how much we were able to __ __. I couldn't believe the __ __ we made—the park looked clean!
Each year volunteers come for the cleanup from everywhere. In 2007 alone, 2,945 people picked up 42,330 pounds of trash and __ __ 132 miles of roadway.
I often hear people __ __ about their surroundings. If you are one of them, I would say the only way to change things is by __ __ rather than complaining. We need to teach by __ __. You can't blame others __ __ you start with yourself.
1.A.distant B.huge C.narrow D.loose
2.A.immediately B.finally C.gradually D.recently
3.A.imagining B.painting C.describing D.climbing
4.A.garden B.home C.lab D.palace
5.A.material B.resources C.waste D.goods
6.A.beyond B.against C.over D.within
7.A.more B.most C.less D.least
8.A.throwing away B.picking up C.breaking down D.digging out
9.A.kill B.save C.wait D.spend
10.A.satisfied with B.delighted in C.tired of D.used to
11.A.something B.anything C.everything D.nothing
12.A.cleanup B.party C.picnic D.concert
13.A.dropped out B.showed up C.looked around D.called back
14.A.demand B.receive C.accomplish D.overcome
15.A.plan B.visit C.contact D.difference
16.A.crossed B.measured C.covered D.designed
17.A.talk B.complain C.argue D.quarrel
18.A.doing B.thinking C.questioning D.watching
19.A.method B.explanation C.example D.research
20.A.although B.if C.when D.unless
高三英语完形填空中等难度题查看答案及解析
When I was seven my father gave me a Timex, my first watch. I loved it, wore it for years, and haven’t had another one since it stopped ticking a decade ago. Why? Because I don’t need one. I have a mobile phone and I’m always near someone with an iPod or something like that. All these devices(装置)tell the time—which is why, if you look around, you’ll see lots of empty wrists; sales of watches to young adults have been going down since 2007.
But while the wise have realized that they don’t need them, others—apparently including some distinguished men of our time—are spending total fortunes on them. Brands such as Rolex, Patek Philippe and Breitling command shocking prices, up to £250.000 for a piece.
This is ridiculous. Expensive cars go faster than cheap cars. Expensive clothes hang better than cheap clothes. But these days all watches tell the time as well as all other watches. Expensive watches come with extra functions—but who needs them? How often do you dive to 300 metres into the sea or need to find your direction in the area around the South Pole? So why pay that much of five years’ school fees for watches that allow you to do these things?
If justice were done, the Swiss watch industry should have closed down when the Japanese discovered how to make accurate watches for a five-pound note. Instead the Swiss reinvented the watch, with the aid of millions of pounds’ worth of advertising, as a message about the man wearing it. Rolexes are for those who spend their weekends climbing icy mountains; a Patek Philippe is for one from a rich or noble family; a Breitling suggests you like to pilot planes across the world.
Watches are now classified as“investments”(投资). A 1994 Philippe recently sold for nearly £350, 000, while the 1960s Rolexes have gone from £15, 000 to £30, 000 plus in a year. But a watch is not an investment. It's a toy for self-satisfaction, a matter of fashion. Prices may keep going up—they’ve been rising for 15 years. But when fashion moves on, the owner of that £350, 000 beauty will suddenly find his pride and joy is no more a good investment than my childhood Timex.
1.It seems ridiculous to the writer that_______________.
A.people dive 300 meters into the sea
B.expensive clothes sell better than cheap ones
C.cheap cars don’t run as fast as expensive ones
D.expensive watches with unnecessary functions still sell
2.What can be learned about Swiss watch industry from the passage?
A.It’s hard for the industry to beat its competitors.
B.It targets rich people as its potential customers.
C.It wastes a huge amount of money in advertising.
D.It’s easy for the industry to reinvent cheap watches.
3.Which would be the best title for the passage?
A.Watches? Not for Me! B.My Childhood Timex
C.Timex or Rolex? D.Watches—a Valuable Collection
高三英语阅读理解中等难度题查看答案及解析
When I was seven my father gave me a Timex, my first watch. I loved it, wore it for years, and haven’t had another one since it stopped ticking a decade ago. Why? Because I don’t need one. I have a mobile phone and I’m always near someone with an iPod or something like that. All these devices(装置)tell the time—which is why, if you look around, you’ll see lots of empty wrists; sales of watches to young adults have been going down since 2007.
But while the wise have realized that they don’t need them, others—apparently including some distinguished men of our time—are spending total fortunes on them. Brands such as Rolex, Patek Philippe and Breitling command shocking prices, up to £250.000 for a piece.
This is ridiculous. Expensive cars go faster than cheap cars. Expensive clothes hang better than cheap clothes. But these days all watches tell the time as well as all other watches. Expensive watches come with extra functions—but who needs them? How often do you dive to 300 metres into the sea or need to find your direction in the area around the South Pole? So why pay that much of five years’ school fees for watches that allow you to do these things?
If justice were done, the Swiss watch industry should have closed down when the Japanese discovered how to make accurate watches for a five-pound note. Instead the Swiss reinvented the watch, with the aid of millions of pounds’ worth of advertising, as a message about the man wearing it. Rolexes are for those who spend their weekends climbing icy mountains; a Patek Philippe is for one from a rich or noble family; a Breitling suggests you like to pilot planes across the world.
Watches are now classified as“investments”(投资). A 1994 Philippe recently sold for nearly £350, 000, while 1960s Rolexes have gone from £15, 000 to £30, 000 plus in a year. But a watch is not an investment. It's a toy for self-satisfaction, a matter of fashion. Prices may keep going up—they’ve been rising for 15 years. But when fashion moves on, the owner of that £350, 000 beauty will suddenly find his pride and joy is no more a good investment than my childhood Timex.
1.It seems ridiculous to the writer that_______________.
A.people dive 300 metres into the sea |
B.expensive clothes sell better than cheap ones |
C.cheap cars don’t run as fast as expensive ones |
D.expensive watches with unnecessary functions still sell |
2.What can be learnt about Swiss watch industry from the passage?
A.It’s hard for the industry to beat its competitors. |
B.It targets rich people as its potential customers. |
C.It wastes a huge amount of money in advertising. |
D.It’s easy for the industry to reinvent cheap watches. |
3.Which would be the best title for the passage?
A.Watches? Not for Me! |
B.My Childhood Timex |
C.Timex or Rolex? |
D.Watches—a Valuable Collection |
高三英语阅读理解极难题查看答案及解析