Ⅴ. 阅读短文,在空白处填入一个适当的单词或括号内单词的正确形式
Over the years, movies and books have used tornadoes a lot in their stories. A tornado can be very dangerous. It usually has wind speeds(风速) of about 100 metres per second, and 20.
travels
(travel) a long distance. Most tornadoes last for less than 10 minutes. 21.
Sadly
(sad), tornadoes kill many people every year.
Scientists can't go inside tornadoes. That means tornadoes are very hard to study. As 22.
a
result, it is still 23.
uncertain
(certain) how tornadoes form and die. 24.
To tell
(tell) how strong a tornado is, scientists look at how much damage it causes and show the levels on the EF-Scale—25.
from
EF0 to EF5. For example, if a tornado only damages trees, it will be at the level of EF0, while a tornado at the 26.
strongest
(strong) level of EF5 blows away buildings with wind speeds of over 100 metres per second.
27.
Since/Because/As
tornadoes can happen very quickly, make sure you know what to do when facing them. When you find 28.
yourself
(you) meeting a tornado, calm down and try to find a safe place inside. Put your hands over the back of your head for 29.
protection
(protect). Also, stay away from windows and heavy things, or they may fall on you.
