问题 多项选择题

变压器高压电源侧复合电压闭锁过电流动作原因()。

A、变压器高压电源侧故障、变压器本体故障,作为瓦斯差动保护的后备保护,它在差动、瓦斯保护拒绝动作的情况下,才动作;

B、中、低压负荷侧母线、出线故障,开关拒动引起越级跳闸;

C、保护回路故障误动作。

答案

参考答案:A, B, C

完形填空

The weather is always different from time to time. Sometimes it is sunny, and sometimes it is      . If you ask me which       weather is my favorite, I would       it’s the snowy days, because I can find many things that make me happy in     times.

I can do many fun things when it snows. If I have a friend       me, we will do anything interesting. All we want to do is to sleep on the ground.       snowmen is a good idea, too. I will make a snowman that looks       my friend, and she will make one that is just like me. I will never       snowball fights. It is my favorite thing       when it snows. When we      to fight, our laughs are everywhere.

I love the snowy days because they make me happy. How about you? Do you like it too?

小题1:A. rainy                   B. snow                 C. fine

小题2: A.lots of                 B. a little                C.kind of

小题3: A. speak             B. say                 C. tell

小题4: A. those                 B. that                 C. this

小题5: A.has                     B. with                     C. and

小题6: A. Taking                 B. Playing                 C. Making

小题7: A. at                     B. like                 C. for

小题8: A. know                 B. remember             C. forget

小题9: A. to do                  B. doing                    C. do

小题10:A. start                     B. began                    C. got

单项选择题