问题补充：
I to help you to do homework but I couldn’t spare any time. I a composition last night and I’ll finish it today.
A. wanted; wrote
B. had wanted; was writing
C. have wanted; wrote
D. wanted; have been writing
答案：
A. wanted; wrote
(答案→)B. had wanted; was writing
C. have wanted; wrote
D. wanted; have been writing
解析：. had wanted表示原本要做某事，从后句I’ll finish it today可知writing动作还没完成用进行时态was writing表示。
