---______do the students exercise a week ?---Once or twice.
#43559
A
How often
B
How long
C
How
D
How many times
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They arrived _____ Wuhan _____ a cold morning.
#39484
A
in; in
B
at; on
C
in; on
D
at; in
I have much work to do. I'm      busy.
#35965
A
a bit of
B
a little
C
a lot
D
a few