用所给词的适当形式填空。   

1. I             (go) to zoo with my friend last Sunday.

2. I like            (swim) in the river in summer.

3. There            (be)a dog and two cats in the room.

4. Which            (season) do you like best?

5. Who is the            (tall) boy in your class?

6. I'm so            (excite). The book is            (excite).

7. Miss Li             (teach) us Chinese this year.

8. It is a             (wind) day today.

9. I often have            (a) apple and            (a) hamburger for mybreakfast.

10. The toy stone is on the            (three) floor.

三相同步发电机与电网并联时，必须满足一些条件，但首先必须绝对满足的条件是（）。

A.相序相同

B.电压相等

C.频率相等

D.励磁方式相同