My father was a worker of a sugar-cane plantation（甘蔗种植园） in Rio Piedras, Puerto Rico. My first job was to drive the oxen that ploughed the cane fields. I would walk behind an ox, guiding him with a stick. For $ 1 a day, I worked eight hours straight, with no food breaks.
Falling and gravity About 400 years ago, Caltleo noticed that objects speed up, or accelerate, as they fall.
He found that heavy and light things, of the same shape and size, take the same time to fall to the ground. Gravity pulls then-* down equally.
Try this for yourself with different objects, like a slipper : and a heavy boot.
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Air resistance Objects of different shapes and sizes fall at different rates. The shape of a parachute makes people fall more slowly.
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| The air pushing against the parachute causes a lot of air resistance*. A person without a parachute falls faster because less air pushes against them. |
The faster something falls, the more air resistance there is on it. Eventually, the air resistance slowing it down becomes as strong as the pull of gravity. Then its speed no longer changes. This is called terminal speed. |
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Free fall If there were no air, there would be no air resistance. All falling objects would just get faster and faster < called is This rate. same the> free fall. | |
67. Falling objects are pulled down to the ground by .
A. gravity B. resistance C. speed D. acceleration（加速度）
68. Why do people make parachutes（降落伞）?
A. To look pretty and colourful in the air. B. To slow down the falling speed.
C. To push against the air in the sky. D. To accelerate the falling movement.
69. Which did Galileo discover?
A. A heavy ball falls faster than a light ball. B. A light ball falls faster than a heavy ball.
C. A light ball and a heavy ball fall at the same speed
D. A light ball and a heavy ball fall at different speed.
70. Which of the following is NOT true according to the passage？
A. Heavy and light objects fall equally when they are different in size.
B. When air resistance equals gravity, objects fall at terminal speed.
C. Without air; all falling objects get faster and faster at the same rate.
D. Slippers（拖鞋） and boots （靴子）fall at the same speed because they have the same shape
So, in eighteen fifty-seven, D.C. Lawmakers in Congress（国会） in Washington wanted to make it possible to send mail all the way across the United States by land. Congress offered to help any company that would try to deliver mail overland to the West Coast. A man named John Butterfield accepted this offer. He developed plans for a company that would carry the mail―and passengers, too. 
One hundred stagecoaches were built and painted red or dark green. They were the most modern coaches that money could buy. They were designed to hold as many as nine passengers and twelve thousand pieces of mail. The seats inside could be folded down to make beds. Passengers either slept on them or on the bags of mail. 
If I were writing a history of my family, some of the darkest moments recorded would be those about Christmas trees. One would certainly think otherwise; selecting and putting up our trees have always been filled with risk. For example, one afternoon dangerously close to Christmas Eve my mother bought what she thought to be a bargain, a glorious tree that was so full and tall that we could hardly get it into the house. Once we did, my father immediately realized that we would have to hire a carpenter（木匠） to build a stand for it. Another December, perhaps the very next one, we bought a tree earlier than we ever had before. We were happy with its shape and delighted that its size was manageable. We easily placed it in a stand, decorated（装饰） it from top to bottom, and then self-satisfiedly sat back by the fire in its soft light. Two or three days passed and the truth could not be hidden; we had bought a tree cut so long ago that its needles were coming off. There was nothing to do but undecorate it, take it down, and begin tree shopping again. Our most recent Christmas tree offered still another difficult task. When we brought it home, once again it seemed larger than it was in the great outdoors. To complicate matters, we had bought a new stand, one whose nuts （螺帽） and bolts （闩子） worked more mysteriously than those of our old stands. I persuaded two young neighbors to stop playing basketball and to help us get the tree into the house and set it correctly in the stand. Unfortunately, no one noticed the mud on our helpers' shoes, so only after removing several reddish brown spots from the carpet were we able to discuss the question of where the lights and ornaments （装饰物）were stored. Perhaps those who cut their own trees have tales more painful than these. I don't care to hear them, as my family's experiences are enough to cause me to make the following suggestion:" Let's forget the tree next Christmas. Let's simply hang some flowers on the front door and over the mirror in the hall. " 
In the past, people who graduated from college felt proud of their academic（学业的）achievements and confident that their degree would help them to find a good job. My ears are recently full of joyous remarks from my friends such as, “Oh, Beckham is so handsome, so cool, that I can’t help falling in love with him!” Or “What perfect skills he has!” Yeah, I agree 36 some degree, though I sometimes do want to ask them how much they 37 Beckham, apart from his appearance and how much they know about football 38 scoring goals. It seems funny that we are crazy for things, with which we are unfamiliar or 39 which we are uncertain, but we all, my friends 40 I, consider this one of life’s 41 .
We need these pleasures to brighten up our lives. But that doesn’t amount to craziness 42 nonsense（胡闹）. As an old saying 43 : “Don’t judge a book by its cover.” We should not 44 anything from its appearance. We should all know, it is one’s good character and great contribution that 45 one a star and unforgettable. Therefore we’d better say 46 about Beckham’s good looks.
If we close our eyes, 47 in deep thought, we can find that the things that 48 us to be in truth happy, sad or touched 49 a clear meaning. If we don’t go deeper and just satisfied with superficial（表面的）things, 50 we will find that we have not really gained anything 51 our first impression has blinded and misled us, and we’ll remain ignorant（无知） 52 we realize that and make some changes.
It is believed that thinking and going deeper than before is a sign of great 53 . If one day we are willing to go deeper into everything, no matter how much it 54 us, we will finally prove how much we have grown up, how much more sensible（理智的）, mature（成熟的）, and intelligent we have 55 .
| B. on | C. in | D. at |
| B. learn | C. know | D. know about |
| B. except for | C. except | D. apart from |
| B. in | C. about | D. for |
| B. as well as | C. rather than | D. but |
| B. taste | C. sorrow | D. regrets |
| B. and | C. or | D. or else |
| B. talks | C. tells | D. goes |
44. A. take | B. judge | C. accept | D. conclude |
45. A. makes | B. causes | C. builds | D. create |
46. A. better | B. more | C. worse | D. less |
47. A. taking | B. leaving | C. falling | D. getting |
48. A. move | B. change | C. doubt | D. follow |
49. A. lack | B. have | C. include | D. cover |
| B. indeed | C. in a while | D. sooner or later |
| B. even though | C. because | D. although |
| B. although | C. unless | D. if |
| B. progress | C. effort | D. work |
| B. pains | C. delights | D. minds |
| B. made | C. had | D. become |
A. was happening B. happens C. has happened D. happened 
―No, so quickly_________ that I couldn’t get a good look at his face. 
A. knocked B. knocking C. to be knocked D. being knocked 
― Yes, once at a party, but we _______.