— Has Jack finished his homework yet —I have no idea; he ____ it this morning.
（A）was doing
（B）had been doing
（C）has done
（D）did
参考答案
继续答题：下一题
更多大学英语单项选择题库试题
- 1you the editor at the airport?— No, he away before my arrival.
- 2—Tom, this is Hack, Fred is ill in hospital.–fred住院了，这是一个坏消息。 — Oh, _________→ 听者应该表示抱歉。
- 3_______ we go by train or by boat makes no difference.
- 4I’ve never seen droughts on such a large ____________
- 5We know from the passage that Rachel was the author of at least ____.
