.---Where’s that report?-I brought it to you you were in Mr. Black’s office yesterday.

问题补充：

.---Where’s that report?

---I brought it to you you were in Mr. Black’s office yesterday.

A. if

B. when

C. because

D. before

答案：

A. if

(答案→)B. when

C. because

D. before

解析：该空表示“当……的时候”，因此应填when引导时间状语从句。