Although the causes of cancer ____we do not yet have any practical way to prevent it.
#105341
A
are being uncovered
B
have been uncovering
C
are uncovering
D
have uncovered
推荐题目
一Ready to give up guessing，Sandy?一No，no，hold on! I think I______ at the answer now．
#105346
A
arrive
B
am arriving
C
have arrived
D
will arrive
—Joan，what ________ in your hand?—Look！It's a birthday gift for my grandma.
#105314
A
had you held
B
are you holding
C
do you hold
D
will you hold
— ________ for the glass! —It’s OK. I’m wearing shoes.
#105336
A
Look out
B
Walk out
C
Go out
D
get out
----what do you think of the Chinese language today?----Quite popular. It______ in communicating with other countries. More and more foreign friends are learning Chinese.
#105332
A
plays an important role
B
is playing an important role
C
has played an important role
D
is being played an important role
Britain is being ________ in the race for new markets.
#105311
A
left alone
B
left out
C
left behind
D
left over