Experiments of this kind ___in both the U.S and Europe well before the Second World War
#100340
A
had conducted
B
have conducted
C
have been conducted
D
had been conducted
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The 16th Asian Games ____ in Guangzhou from Nov. 12 to Nov. 27, 2010. 
#101383
A
was held
B
was holding
C
will be held
D
will be holding
 The prices are _____ fast these days. Nobody can get the prices _____.
#104710
A
going down; to bring down
B
rising; to be bringing down
C
raising; bring down
D
going up; brought down