—May I         this pair of blue jeans? —Yes, you        .

It was playing video games that took the boy too much time that he          have spent learning．

I want        a book for my granddaughter Linda who is 2 years old.

The well-dressed lady was caught stealing in the fashion shop, Strangely enough,she       have done such a thing.

The room is in a terrible mess; it ________have been cleaned.