1 . During the special period of fighting against the infective illness, you ________ wear a mask when going out.

A．must

B．can

C．need

D．may

2 . I advise you to stay away from Mary. Although she is usually easy-going, she ______be quite annoying sometimes.

A．can

B．need

C．must

D．should

3 . The designer has tried every possible way to make the robot light, so you_______worry about its weight.

A．must

B．may

C．can't

D．needn't

4 . Just as I was hurrying to class, there ________ come Tom with a long story to tell you.

A．could

B．must

C．might

D．would

5 . I guess this book ______ be Mary’s, but I’m not sure.

A．must

B．mustn’t

C．may

D．can

6 . It’s red light now. We _________stop and wait.

A．can

B．must

C．should

D．might

7 . In order to make our dreams come true, we _______ work hard.

A．must

B．can

C．need

D．may

8 . —Mom,_____I hang out with Susan now?
—No,you_____.It’s dangerous for two girls to be outside at night.

A．could;can’t

B．could;needn’t

C．should;can’t

D．must;couldn’t

9 . Public health experts kept telling citizens it was of utmost importance that social distancing and hygiene habits ________ amid the pandemic.

A．were to be kept	B．had to be kept
C．must be kept	D．should be kept

10 . Both drivers and passengers         wear seat belts while their cars are running on the highway.

A．must

B．can

C．may

D．need