--Tree Planting Day is ing. Do you plant trees in spring?
---Yes, many trees in our city every year.
A. are planting
B. are planted
C. were planted
D. will plant
网友回答
A. are planting
(答案→)B. are planted
C. were planted
D. will plant
解析：本题的含义是每年在城市要栽许多树，本题的主语是动作的承受者，故本题用被动结构，结构为be+动词的过去分词，每一年表示一般的情况，故用are planted，故本题选B。