You __________ buy a gift, but you can if you want to.

As it turned out to be the most important meeting in the year, you ____ so casually. 

–What do you think we can do for our parents? --You ____ do anything except to show your love -- a kind word, a warm smile and a helping hand.

--- The T-shirt with Michael Jackson’s picture ____ belong to Tom. He likes him a lot.---No, it ______ be his. He dislikes black colour.

---Must I go to medical school and be doctor like you，Dad？--- No, you __________, son. You’re free to make your own decision.