New technology ______ to make sure that the cars, taxis, buses and trains we use ______ the air.
#104707
A
is used; not to pollute
B
has used; is not polluted
C
is being used; do not pollute
D
has been used; to pollute
推荐题目
Sorry to have kept you waiting. You must have thought ___.
#99981
A
we are not coming
B
we were not coming
C
we did not come
D
we were not come
—Tony, you must have noticed the student who broke the glass.—I'm sorry.I________attentively.
#99685
A
studied
B
was studying
C
am studying
D
would study
When you go to a new country, you must _____ yourself to new manners and customs.
#100880
A
adopt
B
adapt
C
apply
D
afford
Hurry up！Mark and Carol ________ us. (2013·北京，28)
#99436
A
expect
B
are expecting
C
have expected
D
will expect
It was for the first time that the two countries ______ an agreement.
#100479
A
reached
B
have reached
C
had reached
D
will reach