The fiddler crab (蟹) is a living clock. It indicates(=shows) the time of day by the color of its skin, which is dark by day and pale by night. The crab’s changing color follows a regular twenty—four hour plan that exactly matches the daily rhythm (节奏) of the sun.
Does the crab actually keep time, or does its skin simply answer to the sun’s rays, changing color according to the amount of light strikes it? To find out, biologists kept crabs in a dark room for two months. Even without daylight, the crab’s skin color continued to change exactly on time.
This characteristic (特性) probably developed gradually in answer to the daily rising and setting of the sun, to help protect the crab from sunlight and enemies. After millions of years it has become completely regulated (受控制) inside the living body of the crab.
The biologists noticed that once each day the color of the fiddler crab is especially dark, and that each day this happens fifty minutes later than on the day before. From this they discovered that each crab follows not only the rhythm of the sun but also that of the tides (潮水). The crab’s period of greatest darkening is exactly the time of low tide on the beach where it was caught!
1.The fiddler crab is like a clock because it changes color ______.
A. in a regular 24—hour rhythm B. in answer to the sun’s rays
C. at low tide D. every fifty minutes
2.The crab’s changing color ______.
A. tells the crab what time it is B. protects the crab from the sunlight and enemies
C. keeps the crab warm D. is of no real use
3.When the fiddler crabs were kept in the dark , they ______.
A. did not change color B. changed color more quickly
C. changed color more slowly D. changed color on the same timetable
4.The crab’s color—changing ability was probably developed ______.
A. in the process of evolution (进化) B. over millions of years
C. by the work of biologists D. both A and B
5.The best title for this selection would be ______.
A. The Sun and the Tides B. Discoveries in Biology
C. A Living Clock D. A scientific Study
高一英语阅读理解中等难度题
The fiddler crab (蟹) is a living clock. It indicates(=shows) the time of day by the color of its skin, which is dark by day and pale by night. The crab’s changing color follows a regular twenty—four hour plan that exactly matches the daily rhythm (节奏) of the sun.
Does the crab actually keep time, or does its skin simply answer to the sun’s rays, changing color according to the amount of light strikes it? To find out, biologists kept crabs in a dark room for two months. Even without daylight, the crab’s skin color continued to change exactly on time.
This characteristic (特性) probably developed gradually in answer to the daily rising and setting of the sun, to help protect the crab from sunlight and enemies. After millions of years it has become completely regulated (受控制) inside the living body of the crab.
The biologists noticed that once each day the color of the fiddler crab is especially dark, and that each day this happens fifty minutes later than on the day before. From this they discovered that each crab follows not only the rhythm of the sun but also that of the tides (潮水). The crab’s period of greatest darkening is exactly the time of low tide on the beach where it was caught!
1.The fiddler crab is like a clock because it changes color ______.
A. in a regular 24—hour rhythm B. in answer to the sun’s rays
C. at low tide D. every fifty minutes
2.The crab’s changing color ______.
A. tells the crab what time it is B. protects the crab from the sunlight and enemies
C. keeps the crab warm D. is of no real use
3.When the fiddler crabs were kept in the dark , they ______.
A. did not change color B. changed color more quickly
C. changed color more slowly D. changed color on the same timetable
4.The crab’s color—changing ability was probably developed ______.
A. in the process of evolution (进化) B. over millions of years
C. by the work of biologists D. both A and B
5.The best title for this selection would be ______.
A. The Sun and the Tides B. Discoveries in Biology
C. A Living Clock D. A scientific Study
高一英语阅读理解中等难度题查看答案及解析
听下面一段独白，回答以下小题。
1.What is the show about?
A. Gardening. B. Healthy living. C. Virginia tourism.
2.How long will the show last?
A. Four days. B. Nine days. C. Ten days.
3.Where is the show?
A. Behind the zoo. B. In front of the stadium. C. Opposite the Ocean Park.
4.What will Chris Rickens do in the show?
A. Make a speech. B. Organize the show. C. Sell gardening supplies.
高一英语短文中等难度题查看答案及解析
. —I have to get to the post office by six o’clock, but it is almost six now.
— . This clock is fifteen minutes fast.
A. That’s too bad B. Sounds good
C. Sure, you can D. Take it easy
高一英语单项填空简单题查看答案及解析
—I have to get to the post office by six o’clock, but it is almost six now．
—This clock is fifteen minutes fast．
A．That’s too bad B．Sounds good C．Sure, you can D．Take it easy
高一英语单项填空中等难度题查看答案及解析
It was 4 o'clock in the morning when I received the phone call．
“This is the emergency room calling and your son was just36 in with severe burns on his face，neck and arms．We have called for a（n）37and are going to fly him to the burn unit in Seattle．” Seattle was 350 miles from his college，so we knew immediately this was38．
The doctor described the39，which caused the burns．At 6 am，our son and his friends decided to barbecue hamburgers in the courtyard of their apartment．When they 40 the charcoal（木炭），it burst into flames because they had sprayed too much gasoline（petrol）．The flames41my son’s shirt tail and shot from his waist to well over his head．
42，one of the boys was quick-minded，grasped my son，and43him on the grass．While it saved his life，it was not in 44to save him from severe burns and the terrible scars（伤疤）．
After he45from the treatments，the doctors told him they would not do plastic surgery（整容）for 6 months46it takes that long for the skin to stop shrinking and wrinkling．So，he had to return to college with scars typical of severe burns．
When I was a child, my mother told my sister，who had a 10-inch, very 47__ scar on her arm，“Nancy，if you ignore the scar，other people will ignore it．It does not mean they will not48it，but it means it will not matter to them if it doesn’t matter to you．’’
I49this wisdom on to my son．He took my advice to 50and returned to school with his head held high--glad he was alive．
By the end of the six-month waiting period，he decided that the scars did not51, sohe made the52to give up any plastic surgery．
We all have “scars” that we believe53 people to keep away from us．And we spend a lot of time thinking that if only we looked different，or dressed differently，people would like us better．
But you see，people will only judge you by your looks，or your clothes，if you are judging yourself by these same54standards．Put your imperfections out of your mind and concentrate on what you value55yourself，and your beauty will shine through．
1. A．brought B．given C．turned D．showed
2. A．doctor B．hospital C．aircraft D．ambulance
3. A．serious B．terrible C．painful D．important
4. A．event B．process C．reason D．accident
5. A．got B．lit C．burned D．moved
6. A．took B．held C．caught D．attracted
7. A．Fortunately B．Surprisingly C．Happily D．Slowly
8. A．pushed B．threw C．dropped D．rolled
9. A．shape B．place C．fact D．time
10. A．benefited B．recovered C．suffered D．relaxed
11. A．if B．while C．because D．although
12. A．normal B．violent C．obvious D．popular
13. A．mention B．notice C．laugh D．hide
14. A．sent B．kept C．handed D．passed
15. A．heart B．life C．practice D．consideration
16. A．grow B．matter C．exist D．appear
17. A．mistake B．effort C．decision D．request
18. A．invite B．cause C．allow D．remind
19. A．false B．strict C．moral D．general
20. A．by B．over C．beyond D．within
高一英语完型填空中等难度题查看答案及解析
It’s nearly eight o’clock, and the manager ______walk in at any moment.
| A．is possible to | B．is probable to | C．is likely to | D．is able to |
高一英语单项填空中等难度题查看答案及解析
I asked him to come at seven o’clock, but he __________. It’s already eight o’clock．
| A．didn’t show off | B．didn’t show up |
| C．hasn’t shown up | D．hasn’t shown off |
高一英语单项填空中等难度题查看答案及解析
At the crossing there is an arrow _______the direction to the Andrew farm.
A．indicating B．to indicate C．indicated D． dictating
高一英语单项填空中等难度题查看答案及解析
——When is Jay’s concert?
——It’ s_____three o’ clock_____the afternoon of July 18th.
A.at;in B.at;on C.on;in D.in;on
高一英语单项填空中等难度题查看答案及解析
Oh! It’s 9 o’clock! I know________ is no possibility ________ I can catch up with the train.
A.there; that B.it; that C.there; whether D.it; if
高一英语单项填空简单题查看答案及解析