-I think the environment is becoming worse.-Yes, I really don’t know we can do a

—I think the environment is becoming worse.

—Yes, I really don’t know            we can do about it.

试题答案

D

解析试题分析:句意：--我认为环境在变差。--是的，我真的不知道我们对此能做些什么。Know后面是宾语从句，从句缺少do的宾语，排除B、C选项；which强调范围内的选择，而what强调内容，故答案选D。

考点：考查定语从句