—I really don't know what I yesterday without the bike you lent me.—Glad to have been some

问题补充：

—I really don know what I yesterday without the bike you lent me.

—Glad to have been some help to you.

A. could do

B. should have done

C. had done

D. could have done

答案：

A. could do

B. should have done

C. had done

(答案→)D. could have done

解析：考查虚拟语气。因为本句是对昨天的情况进行说明，故使用情态动词+have done的形式，could have done本可以做某事；should have done本应该做某事，实际上却未做；句意：—我真的不知道没有你借我的自行车，我昨天可以做什么。—很高兴能帮到你。故D正确。