Question

【题目】— There is a lot of wind in North China.

— Well, more trees ________ every year to stop the wind.

A. must be planted B. can plant

C. should planted D. must been planted

Answer 1

【答案】A

【解析】

句意：——华北地区的风很多。——嗯，每年必须种植更多的树来抵御大风。主语more trees与动词plant之间是被动的关系，因此要用到被动语态，情态动词被动语态的构成为“情态动词+be+及物动词的过去分词”，只要A符合题意。