Experiments of this kind ___in both the U.S and Europe well before the Second World War.
#102411
A
had conducted
B
have conducted
C
have been conducted
D
had been conducted
推荐题目
It is the first time that Michel _______ the Summer Palace.
#99257
A
is visiting
B
visits
C
has visited
D
will visit
We ________ to go skiing tomorrow，but there’s no snow，so we’ll just stay home instead。
#104762
A
are going
B
were going
C
will go
D
would go
A Du’s unique voice ________ especially to young people.
#101547
A
attracts
B
draws
C
catches
D
appeals
---What’s that noise? ---Oh, my God! I ________ to turn the tap off after I brushed my teeth.
#102233
A
forget
B
forgot
C
was forgetting
D
had forgotten
Since 2012，when he __________，the soldier has been in the army．
#99385
A
had married
B
has married
C
got married
D
is married