—We’redoingalottoprotectourenvironment(环境),butitisnotgo...

问题详情：

—We’re doing a lot to protect our environment(环境), but it is not good enough.

—So we should try______ to look after it.

A. hard             B. harder              C. hardest             D. carefully

【回答】

B

知识点：动词和动词短语

题型：选择题