Every year lots of trees to make our country more beautiful.A. is plantedB. was plantedC.

问题补充：

Every year lots of trees to make our country more beautiful.

A. is planted

B. was planted

C. are planted

D. were planted

答案：

A. is planted

B. was planted

(答案→)C. are planted

D. were planted

解析：本题是考查的是一般现在时的被动语态，故选C