Experiments of this kind _______in both the U.S. and Europe well before the Second World War started.
#100664
A
have conducted
B
have been conducted
C
had conducted
D
had been conducted
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A new cinema ______ here now. They hope to finish it next month.
#103437
A
will be built
B
is built
C
has been built
D
is being built
.--- Have you finished your homework? --- No. I ______ Good Voice of China on Zhejiang TV all day yesterday.
#101817
A
was watching
B
have watched
C
watch
D
would watch
By the time the tornado ended, more than 700 people _________.
#103747
A
have killed
B
had been killed
C
were killed
D
had killed
With all the food supply ___, the researchers had to put an end to the wildlife protection project and returned home.
#103075
A
running out
B
to use up
C
run out of
D
using up
Every possible means ___ to prevent the air pollution, but the sky is still not clear．
#101596
A
is used
B
are used
C
has been used
D
have been used