用所给动词的适当形式填空。

1. The moon _____ get) its light from the sun.

2. —Where is your monitor?"

    —He_____  (make) a model plane in the classroom."

3. What new subjects _____ you _____ (study) next term?

4. The students of Class Four _____ (listen) to a report on science this time yesterday.

5. The rain _____ (not stop) yet. You'd better not go out.

6. Before my father got home, I _____ (finish) my homework.

在 ISO/OSI 参考模型中，网络层的主要功能是______。

A．组织两个会话进程之间的通信，并管理数据的交换

B．数据格式变换、数据加密与解密、数据压缩与恢复

C．路由选择、拥塞控制与网络互连

D．确定进程之间通信的性质，以满足用户的需要