7.Although the causes of cancer ____， we do not yet have any practical way to prevent it.
#105343
A
are being uncovered
B
have been uncovering
C
are uncovering
D
have uncovered
推荐题目
The College Entrance Examination________near, so you should be prepared for it.
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A
is drawing
B
draws
C
drew
D
has drawn
— Who is ____ the TV show? She seems to be talented. — Mary Green, who used to be a great actress.
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A
opening
B
hosting
C
playing
D
seeing
I’m glad to see your health ______ after the operation.
#105301
A
picking up
B
setting up
C
taking up
D
getting up
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
______, your composition is full of mistakes.
#105329
A
Writing carelessly
B
Written carelessly
C
Having written carelessly
D
Being written carelessly