Question

—Lots of trees and flowers ______ on both sides of Huanshan Road last year.
—Oh, that’s beautiful

1. A.
   are planted
2. B.
   were planting
3. C.
   were planted
4. D.
   have planted

Answer 1

C
本题的主语是动作的承受者，要用被动句，本题中有个去年，指的是过去的事件，要用过去时，故本题使用过去时的被动句，结构为was 或were+过去分词，plant的过去分词为planted，故本题选C。