问题 多项选择题

阀损耗的主要部分包括()。

A.阀通态损耗

B.关断损耗

C.阻尼回路和均压回路损耗

D.阀电抗器损耗

答案

参考答案:A, B, C, D

阅读理解

阅读理解。

     Many animals do strange  things  before    an earthquake(地  震).  This news may  be  important.

Earthquakes can kill people and knock down  homes. The animals may help to save lives.

     Some animals make a lot of noise before an earthquake. Farmers have told about this. Dogs  that

are usually quiet have started to howl(吠). Horses on farms have run around in circles. Mice have left

their holes and run away. Cows have given less milk.

     In a town in Italy, cats raced down the street in a group. That happened only a few hours  before

an earthquake. In San Francisco, a man kept tiny pet frogs. One Sunday, the frogs jumped   around

more than ever. They made loud noises, like bigger frogs. That night, an earthquake struck   the  city.

   People want to know when an earthquake is coming. Then they could get away safely. Right now,

there is no sure way to know ahead of time. Maybe the best way is to watch the animals.

1.This story is mostly about _________. 

A.how animals act before an earthquake

B.how an earthquake starts

C.how mice leaves their homes

D.when an earthquake begins

2.Before an earthquake, quiet dogs _________.

A. ran away

B. started to howl

C. climbed trees

D. race down streets

3. Before an earthquake, the frogs _________. 

A. sang

B. left their homes

C. jumped around a lot

D. become quiet

4.There have been earthquakes in _________.

A. most countries    

B. Italy and San Francisco

C. Chicago and Spain  

D. all the western countries

5.People want to _________.

A. be in earthquake        

B. find out early about an earthquake

C. run around in circles    

D. get away from earthquakes

多项选择题