—Your watch is really nice.
—Thank you. I __________it since two years ago.
A. have had B. have bought C. bought
---Must I tell Mike about it?
---No, you _______. He’s already been told.
| A．mustn’t | B．can’t |
| C．needn’t | D．shouldn’t |
We brush our teeth twice a day.
| A．may | B．can | C．should | D．shouldn’t |
My mother is ill. I ______ stay at home to take care of her.
| A． can | B．may | C．have to | D．maybe |
—Is Mr. Smith over there?
—It ________ be him. He has gone to Beijing on business.
| A．can't | B．must | C．might | D．can |
After a long walk, the old man be tired now.
| A．can’t | B．must |
| C．has to | D．need |