I don’t remember when and where Ithis umbrella.A. boughtB. buyC. have boughtD. had bought

问题补充：

I don’t remember when and where Ithis umbrella.

A. bought

B. buy

C. have bought

D. had bought

答案：

(答案→)A. bought

B. buy

C. have bought

D. had bought

解析：我不记得是在什么时候在哪儿买的这把伞了。结合语境可知从句描述的是过去某时发生的动作，故用一般过去时态。选A。