We all know that zebras have stripes (条纹). However, both animal experts and zebra fans all over the world haven’t known the reason for centuries. But now it appears that some researchers in California may have finally solved the age-old mystery!
In order to find the reason why zebras have stripes, a team of scientists led by Professor Tim Caro set to work. They began by comparing the thickness, location, and the stripes on seven species of zebras that live in various geographic locations. They then examined some factors that may continuously affect zebras, such as their natural enemies, the temperatures of their living places and the small insects around them like flies. To their amazement, the only factor that was linked with the stripes was the annoying flies. The zebras with the most obvious and the largest number of stripes mostly live in areas with more flies.
But that led to another question: why are zebras the only kind of animal smart enough to develop the stripes? After all, there are plenty of other animals like horses and donkeys, which are facing the same trouble. Upon closer examination of the black and white animals, the researchers noticed that unlike the others, zebras have very short coats of hair, making them particularly easy to be bitten (咬) by the flies!
While Tim says that this mystery is finally solved, it has given rise to a new one. Why are these fearless flies that have no fears of attacking animals that are thousands of times bigger, afraid of black and white stripes? If you have any answer, be sure to add it to the comments below. It may help the professor with his new research!
1.What does the underlined phrase in Paragraph 2 mean ________?
A.was connected with B.was different from
C.was similar to D.was harmful to
2.Why are zebras easy to be bitten?
A.They have very short coats of hair. B.They have a special smell.
C.They are very tall and strong. D.They live in dangerous places.
3.What will Tim study next?
A.Why flies like attacking zebras.
B.Why flies don’t attack horses or donkeys.
C.Why flies like attacking bigger animals.
D.Why flies are frightened of black and white stripes.
4.What does the passage mainly talk about?
A.The living habits of zebras. B.How zebras deal with flies.
C.Why zebras have stripes D.People’s comments on zebras.
九年级英语阅读单选中等难度题
We all know that zebras have stripes (条纹). However, both animal experts and zebra fans all over the world haven’t known the reason for centuries. But now it appears that some researchers in California may have finally solved the age-old mystery!
In order to find the reason why zebras have stripes, a team of scientists led by Professor Tim Caro set to work. They began by comparing the thickness, location, and the stripes on seven species of zebras that live in various geographic locations. They then examined some factors that may continuously affect zebras, such as their natural enemies, the temperatures of their living places and the small insects around them like flies. To their amazement, the only factor that was linked with the stripes was the annoying flies. The zebras with the most obvious and the largest number of stripes mostly live in areas with more flies.
But that led to another question: why are zebras the only kind of animal smart enough to develop the stripes? After all, there are plenty of other animals like horses and donkeys, which are facing the same trouble. Upon closer examination of the black and white animals, the researchers noticed that unlike the others, zebras have very short coats of hair, making them particularly easy to be bitten (咬) by the flies!
While Tim says that this mystery is finally solved, it has given rise to a new one. Why are these fearless flies that have no fears of attacking animals that are thousands of times bigger, afraid of black and white stripes? If you have any answer, be sure to add it to the comments below. It may help the professor with his new research!
1.What does the underlined phrase in Paragraph 2 mean ________?
A.was connected with B.was different from
C.was similar to D.was harmful to
2.Why are zebras easy to be bitten?
A.They have very short coats of hair. B.They have a special smell.
C.They are very tall and strong. D.They live in dangerous places.
3.What will Tim study next?
A.Why flies like attacking zebras.
B.Why flies don’t attack horses or donkeys.
C.Why flies like attacking bigger animals.
D.Why flies are frightened of black and white stripes.
4.What does the passage mainly talk about?
A.The living habits of zebras. B.How zebras deal with flies.
C.Why zebras have stripes D.People’s comments on zebras.
九年级英语阅读单选中等难度题查看答案及解析
We all know that lying (说谎) is wrong. But do you know that it is bad for both your physical and mental health? A recent study shows that telling fewer lies helps people physically and mentally.
“For ten weeks, 110 people aged from 18 to 71 were tested to see the relationship between the number of lies they told and their health,” said Anita Kelly, a professor at the University of Notre Dame in Indiana. “When they lied more, their health declined,” said Kelly.
Researchers divided the people into two groups. Group A was told to avoid telling any lie for any reason to anyone. They may omit (忽略) the truth, refuse to answer questions, and keep secrets, but they can’t say anything that they know are not true. Group B was not told anything like this.
Over the study period, when people in Group A told fewer lies in a week than they did in other weeks, they experienced fewer health problems such as sore throats and headaches. Professor Linda Stroh said, “When you find that you don’t lie, you have less stress (压力).” The results of past research show that each American tells about 11 lies a week. In both groups, when people lied less during a week, they reported better physical and mental health during that period.
“It’s certainly a good thing to have people be more honest,” said Robert Feldman of the University of Massachusetts. “It may improve our mental health, but I don’t think it can improve our physical health.”
1.The underlined word “declined” means “________” in Chinese.
A. 变坏 B. 改善 C. 加强 D. 混乱
2.From the second paragraph, we can learn that ________.
A. the test continued for no more than one month
B. older people lie less than younger people
C. the number of lies one tells can affect one’s health
D. many people feel sick when they don’t tell lies
3.People in Group A were allowed to ________.
① omit the truth ② refuse to answer questions
③ keep secrets ④ tell lies to strangers
A. ①②③ B. ②③④ C. ①②④ D. ①③④
4.According to Linda Stroh, ________.
A. mental health is more important than physical health
B. when people don’t lie, they feel more relaxed
C. to be honest can’t improve our physical health
D. telling lies is necessary sometimes
5.We would most probably find this passage ________.
A. on a travel website B. in a story book
C. in a health magazine D. in a cookbook
九年级英语阅读单选中等难度题查看答案及解析
We did not know you were in trouble at that time, we would have given you a hand.
A. however B. otherwise C. instead D. moreover
九年级英语单选题中等难度题查看答案及解析
We all know that Changjiang River is longer than ___________ in America.
A.any other rivers B.any other river
C.any rivers D.any river
九年级英语单项填空中等难度题查看答案及解析
______ there any living things on other planets？
I have no ideas．Maybe we can know more about that in the future．（ ）
A．Is B．Are
C．Has D．Have
九年级英语单项填空中等难度题查看答案及解析
As we all know that our parents have jobs that keep them busy almost all day long. Sometimes they only have a ________ day in a week. It doesn't allow them to keep an________on their children.
Most of the children today are too________,because they are given too much freedom by their families. This is their parents'________.They should know that the________they give to their children is misunderstood. It can lead them to a wrong way.
For example, it is________for a 17-year-old child to go out in the evening on weekends. Parents are also guilty（内疚的）of the way their children show up in the street or at school. The same guilt________the teaching system as well. Pupils shouldn't be allowed to________like they were on a fashion show at school.
Another important fact is that children are free to________money. Parents shouldn't allow their children to have________pocket money.
I think children are given too much freedom not only by their parents, but also by the society.
1.A.boring B.free C.pleasant D.bright
2.A.idea B.ear C.eye D.hour
3.A.patient B.rude C.fat D.serious
4.A.mistake B.order C.information D.advice
5.A.money B.pressure C.freedom D.schoolwork
6.A.careful B.safe C.pleasant D.dangerous
7.A.belongs to B.gives up C.gives to D.sets up
8.A.buy B.dress C.taste D.look
9.A.have B.steal C.make D.spend
10.A.too many B.a bit C.too much D.a little
九年级英语完型填空中等难度题查看答案及解析
We all know that many women like to wear dresses in different colors and popular styles,but have you ever heard of a 4D dress?
Jessica Rosenkrantz in the USA used 3D printing technology to make a very special dress. The dress maker called the special dress a“4D dress”. It is like the fabric(织物). It can turn into different kinds of shapes.
The company, in Massachusetts, the USA, also made a smart phone and an app(应用). They can help women to control their dresses. If women use the phone and the app, they can change the colour, the style and many other things of the dresses. Isn't it very interesting?
When she talked about her work, Jessica said,“There will be many more changeable dresses for women in the future. I am interested in making them too, I can't wait to make different kinds of new dresses for women.”
1.What will the 4D dress do for women?
A.It will make women relax themselves a lot. B.It will turn into different styles for women.
C.It will help women keep thin and beautiful. D.It will help women find good jobs easily.
2.What does the underlined word “It”in the passage refer to?
A.The 4D dress. B.3D printing technology.
C.A company. D.The dress maker.
3.What will Jessica do in the future?
A.She will have many companies around the world.
B.She will buy a very new smart phone and use the app.
C.She will make many more changeable dresses.
D.She will help women choose more beautiful dresses.
4.From the passage, we can infer（推断）that _________________.
A.Jessica Rosenkrantz used a common thing to make the 4D dress
B.the 4D dress can only turn into ten kinds of shapes for women
C.the company in the UK made the smart phone to control the 4D dress
D.women may use the phone and the app to change the style of the dress
5.What's the best title for this passage?
A.Women's hobbies B.Women's styles
C.Jessica's dream D.The 4D dress
九年级英语阅读单选中等难度题查看答案及解析
根据下面短文内容，在短文的空格处填上一个恰当的词，使短文完整、通顺。
Dear boys and girls, as we all know that all of you have got the chance to study online because of the serious situation around China. How exciting it is for many of you guys! 1., along with the excitement, you may meet some problems like spending too much time playing games while having online classes and so on. These problems might make 2. impossible for you to study well. So what can we do to improve our online studies? Here are some pieces of advice for you.
Ensure a good connection
To me, the biggest headache about studying online is the poor quality of my Internet connection. 3. one of my online classes, I couldn’t hear my English teacher’s voice and I had to reconnect. It wasted lots of time. Since then, I have checked my network before class every day and asked other family members not to use the 4. while I’m having a class. (Zhao Yuchen, 13, Beijing )
5. your time properly
Studying at home has made it hard for me to plan my time. I had a hard time planning my course timetable at first. Planning 6.of time and creating a study calendar is very important. You need to estimate (估计) how much time each task will 7., review your class content(内容), ask questions and take notes, and make a to-do list before doing your homework. These are all good ways to help us learn better online. (Lin Xiyu, 14, Shanghai)
No distractions(分心)
Online learning takes strong self-discipline (自律) and willpower. There are lots of distractions while studying at home. My mom likes to offer me snacks and drinks, which sometimes distracts me from listening during my classes. I have asked her to stop interrupting (干扰) me while I’m studying. A 8. room and clean desk can help us pay full attention to what we do. (Zhang Penghui, 15, Heilongjiang)
九年级英语单词填空中等难度题查看答案及解析
If you have _____ questions, please put up your hands.
A. some B. both C. all D. any
九年级英语单项填空中等难度题查看答案及解析
As we all know, blood is very important to people.However, there isn 't always enough blood for people’s use. So giving blood seems necessary.
81-year-old James Harrison, also known as the man with the golden arm, not only has given his blood, but also has been doing that for about 60 years! When Harrison was young, he was in hospital for a few months.The blood he received saved his life so he decided to give blood.
Recently he has just stopped doing that. During the past few years, he has saved the lives of more than 2.4 million babies by giving his blood. Harrison 's blood contains something special that can be used to develop medicine to prevent unborn babies from dying of blood diseases.
In fact, a number of newborn babies are easy to get some kinds of blood diseases. Just because of Harrison, many new mothers can see the hope of saving their babies. Giving blood is a kind of great charity. Harrison is always glad and ready to do it. But now he has passed the age limit (年龄限制) for donors to continue giving blood in Australia. Harrison has made his 1,173rd and final donation recently.
He holds Guinness World Records for the number of donations he made, and the Australian Red Cross Blood Service said, “ As a blood donor, his kindness leaves us a lot of treasure and changes lives of many babies.”
In 1999，Mr Harrison received the Medal of the Order of Australia for his“amazing and selfless (无私的)support of the blood service"”.
1.Why did James decide to donate blood?
A. His parents asked him to do that. B. He is the man with the golden arm.
C. Someone else's blood saved his life. D. He could get lots of money.
2.What do you think of James?
A. He is very kind . B. He is very brave.
C. He is very lazy D. He is very mean.
3.What might the underlined word “donors” mean in Chinese?
A. 商人 B. 执法者 C. 管理者 D. 献血者
4.What’s the best title for the passage?
A. A great blood donor. B. A kind of special blood.
C. Giving away blood in Australia. D. Saving unborn babies.
九年级英语阅读单选困难题查看答案及解析