Although the causes of cancer_____, we do not yet have any practical way to prevent it.
#104936
A
are being uncovered
B
have been uncovering
C
are uncovering
D
have uncovered
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The vegetables didn’t taste very good. They  _______ too long.
#100525
A
had been cooked
B
were cooked
C
have cooked
D
cooked
----Have you ever seen Peter recently ?---Yes . He _____ me to ask you how you _____ along with your new job these days . 
#104923
A
has asked ; have been getting
B
asked ; were getting
C
often asks ; are getting
D
asked ; are getting