用所给单词的正确形式填空。

1. It takes about ten______ (minute) to walk to school.

2. We enjoyed______ (we) that day.

3. He is very______ (friend) to us.

4. There are some______ (sheep) on the hill.

5. Taking a plane is______ (quick) than taking a train.

运行中的电压互感器二次回路电压降应定期进行检验。对35kV及以上电压互感器二次回路电压降至少每（）年检验一次。

A.1；

B.2；

C.3；

D.5。