（）为封闭式结构，适用于无天花板且电磁干扰比较严重的布线环境

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问题单项选择题

（）为封闭式结构，适用于无天花板且电磁干扰比较严重的布线环境。但对系统扩充、修改和维护比较困难。

A.梯级式桥架

B.槽式桥架

C.托盘式桥架

D.组合式桥架

答案

参考答案：B

填空题

用所给词的适当形式填空。

1. —Why are you so (excite)?

—Because we win the game.

2. Amy, (not talk) in class.

3. Water is very important for us. We can’t live (with) it.

4. —Who is the ______(one ) to come to school?

—Oh, it’s Lily.

5. There are lots of potatoes on those (shelf).

6. Do you know the girl (call) Kitty?

7. Listen! Someone (knock) at the door.

8. All the walkmans on the desk are those ______ (play).

9. Let him (clean) the blackboard today.

10. Miss Chen teaches (we) English this term.

问答题简答题

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