Doing your homework is a sure way to improve your test scores, and this is especially true ________ it comes to classroom tests.

A. as              B. since       C. when    D. after

My brother is very good ___ ping-pong.

        A.in       B.for       C. at          D.on

We make sure we’re always well stocked up with candles, just ________.

A. in case B. for certain   C. in practice   D. for use

Comrade Wang ________ be in Shanghai—I saw him in the company only a few minutes ago.

A. mustn’t        B. can’t    C. may not        D. isn’t able to

There are several research centers in China ________ a certain disease called Bird Flu is being studied.

A. which       B. where    C. when     D. what

It seems oil _____from this pipe for some time, we’ll have to take the machine apart to put           it right.

A．had leaked       B．is leaking  C．leaked      D．has been leaking

I _______ in London for many years, but I’ve never regretted my final decision to move back to China.

A. lived   B. was living　

C. have lived  D. had lived

Mrs. Brown was much disappointed to see the washing machine she had had ____ went wrong again.

       A. it to repair         B. it repaired        

    C. repaired            D. to be repaired

_____ this instrument should have put its work permit number on the box.

A. Who checked   B. Whoever inspected

C. No matter who examined   D. Those who estimates

The house built of stone lasts longer than ____ built of wood.

   A. the one B. one C. that D. its