阅读理解

　　Even if you are a good high-jumper, you can jump only about seven feet off the ground. You cannot jump any higher because the earth pulls you hard. The pull of the earth is called gravity.

　　You can easily find out the pull of the earth. If you weigh (称体重) yourself, you will know how much gravity is pulling you.

　　Since there is gravity, water runs downhill. When you throw a ball into the air, it falls back down. Because of gravity you don't fall off the earth as it whirls (旋转) around.

　　Then, can we get away from the earth and go far out into space? Now you can do it, because spaceships have been invented. The spaceship will go so fast that it can escape (逃离)the earth's gravity and carry you into space.

(1) In this passage (文章), the word “gravity” means

[　　]

A. the pull of everything

B. the force (力) which attracts (吸引) the earth towards us

C. the force of attraction among things

D. the force which attracts things towards the center of the earth

(2) When you slip (滑倒)on something, you

[　　]

A. always fall down to the ground

B. sometimes fall down to the ground

C. go up into the air

D. often fall off the earth

(3) Gravity is so strong that ________

[　　]

A. it can't make you throw a ball into the air

B. it can keep everything on the earth

C. you can jump at least seven feet high

D. you can't go up into the air by spaceship

(4) Because of “gravity ”,________

[　　]

A. water flows (流) everywhere

B. we can go everywhere by ship

C. water flows downwards on the earth

D. water flows at the foot of hills

(5) We can get away from the earth by spaceship because

[　　]

A. the spaceship goes very fast

B. the earth has no gravity to the spaceship

C. the spaceship has a strange energy (能量)

D. the spaceship can go higher than any other thing on the earth

阅读理解

　　Even if you are a good high-jumper, you can jump only about seven feet off the ground. You cannot jump any higher because the earth pulls you hard. The pull of the earth is called gravity.

　　You can easily find out the pull of the earth. If you weigh (称体重) yourself, you will know how much gravity is pulling you.

　　Since there is gravity, water runs downhill. When you throw a ball into the air, it falls back down. Because of gravity you don't fall off the earth as it whirls (旋转) around.

　　Then, can we get away from the earth and go far out into space? Now you can do it, because spaceships have been invented. The spaceship will go so fast that it can escape (逃离)the earth's gravity and carry you into space.

(1) In this passage (文章), the word “gravity” means

[　　]

A. the pull of everything

B. the force (力) which attracts (吸引) the earth towards us

C. the force of attraction among things

D. the force which attracts things towards the center of the earth

(2) When you slip (滑倒)on something, you

[　　]

A. always fall down to the ground

B. sometimes fall down to the ground

C. go up into the air

D. often fall off the earth

(3) Gravity is so strong that ________

[　　]

A. it can't make you throw a ball into the air

B. it can keep everything on the earth

C. you can jump at least seven feet high

D. you can't go up into the air by spaceship

(4) Because of “gravity ”,________

[　　]

A. water flows (流) everywhere

B. we can go everywhere by ship

C. water flows downwards on the earth

D. water flows at the foot of hills

(5) We can get away from the earth by spaceship because

[　　]

A. the spaceship goes very fast

B. the earth has no gravity to the spaceship

C. the spaceship has a strange energy (能量)

D. the spaceship can go higher than any other thing on the earth