※not everybody属于部分否定，表示"并不是所有人"。

⑳light v.点燃(lit，lit)　 \s\up2(21(21)clear vi.(烟雾)消散

\s\up2(22(22)disappear vi.消失

※句中No one属于全部否定，表示"没有人"。what引导的从句在此作knows的宾语，且在从句中作主语。

※现在分词短语作结果状语，表示自然而然的结果。

Read the text carefully and choose the best answer.

1.Of the uses of the rockets，which one is NOT mentioned?

A.In battles.

B.In firework displays.

C.In sending visitors into space.

D.In the military.

2.Rockets were probably invented ________about 2，000 years ago.

A.in surprise　　　　　 B.on purpose

C.by chance D.by mistake

3.One Italian scientist invented a rocket which________.

A.could fly into the sky

B.could hit the enemy's horse

C.could fly over the surface of water

D.could clear the cloud in the air

4.What's the topic of the text?

A.The dangers of rockets.

B.The development of rockets.