4．cause vt.引起；导致

5．furniture n．家具

6．bury vt.埋葬

7．occur vi.发生

8．tropical adj.热带的

9．violent adj.猛烈的；激烈的；强烈的

violence n．暴力

10．strike vt.& n．(雷电、暴风雨等)袭击

Ⅱ.重点短语

1．pick up卷起；掀起；拾起，捡起；接收；无意中学会

2．take off去掉；脱下；起飞；取下

3．on average平均起来

4．of all time有史以来

5．end up结果为......，以......结束

Ⅲ.重点句式

1．leave＋宾语＋宾补

They can destroy houses，but leave the furniture inside exactly where it was.

它们能毁掉房子，却把房内的家具留在原处。

2．现在分词(短语)作结果状语

On average，there are 800 tornadoes in the US each year，causing about 80 deaths and 1,500 injuries.

平均来说，美国每年发生800次龙卷风，造成大约80人死亡，1 500人受伤。

3．by the time引导时间状语从句

By the time it ended，more than 700 people had been killed(kill) and 2,700 had been injured (injure)．

等到风停时，已有700人死亡，2 700人受伤。

Ⅰ.课文判断正(T)误(F)

1．All tornadoes have winds of more than 400 kilometers per hour.(F)

2．There are more tornadoes occurring in the US than in other parts of the world.(T)

3．Tornadoes can't destroy furniture because they are not violent enough.(F)

4．In the US，there are usually about 80 people killed in tornadoes every year.(F)