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科目:高中英語(yǔ) 來源: 題型:
If you drop a feather and a hammer ( 鐵錘) , which do you think will hit the ground first?
On his last moon walk in 1971,Apollo 15's Commander David Scott did his final 21 for the television cameras. Scott was re-creating an experiment 22 by the astronomer Galileo in 1590.
If you guess that the 23 would hit the ground first,you' re not alone. When Galileo was a boy,everyone 24 that heavier things fell faster. A rock twice as heavy as a potato should fall twice as fast. That's what they 25 in school.
But Galileo wasn’ t so 26 . So he decided to 27 it. He dropped balls of different 28 from towers and timed how long they took to get to the ground. And he discovered 29 amazing — dropped things fall at the same rate,no matter how 30 they are.
Why? Falling objects fall 31 the pull of gravity between the object and Earth. And the tremendous (巨大的) force of Earth's gravity is the same whether it's 32 on a feather or a hammer.
But wait,you say — feathers do fall more 33 than hammers. That's quite true,on Earth — but the 34 is air,not gravity. Air pushes against light feathers enough to hold them up,but it isn't 35 enough to hold up a heavy hammer. This pushing of air 36 people for a long time.
The moon has no 37 to slow a falling object. But it does have gravity. The moon's gravity is 38than Earth's,since the,moon is smaller. But it's still strong enough for dropping things.
And sure enough,when Scott let the hammer and the feather drop,they hit the ground 一 exactly 39.
“Galileo was 40 in his findings/' Scott broadcast. .
21. A. practice B. interview
C. experiment D. flight
22. A. ignored B. given up
C. reported D. thought up
23. A. feather B. hammer C. camera D. rock
24. A. doubted B. believed
C. denied D. forgot
25. A. taught B. lost C. learned D. recorded
26. A. sure B. sad C. nervous D. lucky
27. A. imagine B. design
C. name D. test
28. A. sizes B. shapes C. colors D. weights
29. A. anything B. nothing
C. something D. everything
30. A. soft B. heavy C. long D. beautiful
31. A. instead of B. because of
C. in case of D. in spite of
32. A. depending B. focusing
C. pulling D. relying
33. A. gently B. steadily
C. slowly D. naturally
34. A. reason B. problem
C. goal D. winner
35. A. good B. big C. clean D. strong
36. A. informed B. fooled
C. reminded D. persuaded
37. A. energy B. time C. life D. air
38. A. greater B. older C. weaker D. severer
39. A. alone B. together
C. silently D. loudly
40. A. brave B. curious
C. correct D. humorous
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科目:高中英語(yǔ) 來源: 題型:
I .根據(jù)語(yǔ)境,從方框中選擇恰當(dāng)?shù)膯卧~填空,有的需要變換形式。
passenger,onto,trouble,hit
1. You’re just asking for if you don’t give them the money.
2. The number of flying on planes in the country has increased (增長(zhǎng))by 35 percent in the past six years.
3. Mary Mike on the head with a book by accident.
4. 一I’11 see you the train.
—Thank you.
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科目:高中英語(yǔ) 來源: 題型:
4. Whenever Maty reads an interesting story,she can't keep it to and wants to share it with her friends.
A. she B. her
C. hers D. herself (2015 河南)
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科目:高中英語(yǔ) 來源: 題型:
2. —You decided to go to Qingdao on vacation?
一Yeah!We made the d yesterday.
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科目:高中英語(yǔ) 來源: 題型:
() 30. When I arrived at home,I saw him the 2015 FI VB Volleyball Women's World Cup.
A. watch B. watching C. watched D. to watch
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