Experiments of this kind in both the U．S．and Europe well before the Second World War．
#102432
A
have conducted
B
have been conducted
C
had conducted
D
had been conducted
推荐题目
Our earth is getting warmer and warmer. It is time for us to_____ the emission(排放) of CO2.
#99319
A
break down
B
cut in
C
cut down
D
cut off
When he was alive, the old scientist used to say that knowledge ＿＿＿＿from practice and he gained his experience by doing a lot of practical work.
#104636
A
was coming
B
had come
C
comes
D
would come
As soon as I got on the bus I realized that I________ my papers in the house.
#103345
A
left
B
was leaving
C
had left
D
have left
—So what is the procedure?—All the applicants ________ before a final decision is made by the authority.(2013·北京，32)
#99435
A
interview
B
are interviewing
C
are interviewed
D
are being interviewed
—Have you ever heard that Beijing toilet attendants will be required to learn English for the 2008 Olympic Games?—Yeah, I ___ about it in The Beijing Morning Post.
#103704
A
had read
B
read
C
would read
D
will read