完形填空。 Even if you are a good high-jumper, you can jump only about seven __ 1 __ off the ground. You cannot  jump any higher because the earth __ 2 __ you hard. The pull of the earth is__ 3 __  gravity (引力). You can easily __ 4 __ out the pull of the earth. If you weigh __ 5 __  , you will know how__ 6 __ gravity is pulling you. Since there is gravity, water runs downhill. when you__ 7 _ a ball into the air, it falls back down. Because of gravity, you do not fall off the earth __ 8 __  it turns around. Then, can you get __ 9 __  from the earth and go far out into space? Now you can do it, because spaceships have been invented. The spaceship will go fast that it can get rid of (除掉) the earth's gravity and __ 10 __ you into space. (     ) 1. A. kilometer (     ) 2. A. pulls (     ) 3. A. said (     ) 4. A. find (     ) 5. A. myself (     ) 6. A. much (     ) 7. A. fly (     ) 8. A. as (     ) 9. A. off (     ) 10. A. get B. foot B. push B. called B. look B. yourselves B. many B. throw B. and B. away B. bring C. feet C. makes C. told C. saw C. you C. heavy C. get C. because C. lost C. carry D. kilometers D. hits D. spoken D. watch D. yourself D. long D. make D. or D. left D. throw