－Is it good to look up every new word when I come across it in reading?

－No．You ________ because you are likely to guess the meaning from the context．

A．can’t

B．mustn’t

C．don’t have to

D．ought not to

A computer ________ think for itself．It must be told what to do．

A．can’t

B．couldn’t

C．may not

D．might not

How ________ you say that you really understand the whole story if you have covered only part of the article?

A．can

B．must

C．need

D．may

A left-luggage office is a place where bags ________ be left for a short time, especially at a railway station．

A．should

B．can

C．must

D．will

Mr．Bush is on time for everything．How ________ it be that he was late for the opening ceremony?

A．can

B．should

C．may

D．must

－Will you stay for lunch?

－Sorry, ________．My brother is coming to see me．

A．I mustn’t

B．I can’t

C．I needn’t

D．I won’t

The policeman told the pupils, “You ________ play football in the street．”

A．can’t

B．needn’t

C．mustn’t

D．shouldn’t

I have neither a raincoat nor an umbrella．That’s why I ________ wait until the rain stops．

A．must

B．should

C．ought to

D．have to

－Must I finish the exercises in class?

－No, you ________．

A．mustn’t

B．don’t have to

C．won’t

D．shouldn’t

－Shall I help you with that suitcase?

－________．

A．It’s all right, thanks

B．Yes, go ahead, please

C．I don’t want to trouble you too much

D．No, please don’t do it