You ______ be very tired. You have worked for quite a long time.

[    ]

A. have to   B. must   C. has to   D. mustn't

The encouragement and complete trust of the teacher is ______ the poor student needs most.

[    ]

A. that   B. what   C. all what   D. which

It's impolite to interrupt _______ others are speaking.

[    ]

A. as   B. since   C. while   D. as long as

You should listen with complete attention even though you don't agree with ____ she or he says.

[    ]

A. that   B. what   C. which   D. how

Johnny, you ______ play with the knife, you ____ hurt yourself.

[    ]

A. won't; can't　　 B. mustn't; may

C. shouldn't; must  D. can't; shouldn't

Before you start a book, make sure that it is ____ you can easily read and understand.

[    ]

A. one   B. it   C. that   D. so

— ____I open the door for you? 

— No, thanks. I can manage.

[    ]

A. Shall   B . Will   C. Can   D. Would

You should't read the book that you are interested in ______ a travel book.

[    ]

A. the same  B. the same way  C. the same way as  D. the same as

It was not safe to travel ______ in the forest near the coast. 

[    ] 　　

A. lonely　　B. oneself　　 C. alone　　 D. only

This is the third time we ________ improvement (改进) in that machine .

[　　]

A．had made

B．have made

C．are making

D．would have