With the help of high technology, more and more new substances ___in the past few years.
#101737
A
discovered
B
have discovered
C
had been discovered
D
have been discovered
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---- What’s that noise?       ---- Oh, I forgot to tell you. The new machine ______.
#102011
A
was tested
B
will be tested
C
is being tested
D
has been tested
---Are you still busy?---Yes, I _______my work, and it won’t take long.
#100104
A
Just finish
B
am just finishing
C
have just finished
D
just finished