Although the causes of cancer ________, we do not yet have any practical way to prevent it．

Although the causes of cancer ________, we do not yet have any practical way to prevent it．

#103264

have uncovered

have been uncovering

are uncovering

are being uncovered

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Tom is going to talk about the World Expo in Shanghai, but I’d rather he ______ on the World Cup.

#103510

focus

focused

had focused

would focus

I called him many times, but I didn’t get through, maybe his mum _   on the phone all the time．

#101393

talked

was talking

has talked

had talked

I hope____________  the job she's applied for（申请）.

#104875

she's going to get

she'll get

she is to get

she decides to get

The boy whom you lent the bike to ____ by a car.

#102695

hit

be hit

having been hit

was hit

 The teacher _____ the students how to improve their writing skill since last term.

#100982

has told

is telling

has been telling

will have told

共5993题