问题 多项选择题

短路电流计算中,下列假设条件正确的是( )。

A.三相系统对称运行;

B.各电源的电动势相位相同;

C.各元件的磁路不饱和;

D.同步电机不设自动励磁装置。

答案

参考答案:A,B,C

完形填空

Most Canadian families love to have holidays   summer. Summer is a good season   holidays. It is very hot during the months of July and August. Children do not have any classes during these   months.

Some    like to stay at home during the holiday. They work in the garden, visit friends,    books, or    TV. Many families    their lunch to a park or somewhere far   the city. They like to eat where there are many trees or there is a nice lake. If they live near the sea, they often go to the beach. They can fish, swim or enjoy the sun there.

Canada is a large country. Many families travel by    or by train to see interesting places. They also travel by plane to a foreign country. Many big cities have many famous buildings, theatres, shops and other places   travelers.

小题1:A. for            B. in             C. on

小题2:A. to             B. of             C. for

小题3:A. one            B. two           C. three

小题4:A. people         B. peoples        C. man

小题5:A. see           B. watch         C. read

小题6:A. see            B. watch         C. look

小题7:A. takes          B. take           C. look

小题8:A. from          B. away           C. to

小题9:A. car            B. a car           C. their car

小题10:A. for            B. in            C. on

单项选择题