Nothing can be done _______ he returns.
#56142
A
as
B
before
C
while
D
until
推荐题目
Kate's dad is getting old. She will go back home to see him _____it is convenient.
#56242
A
because
B
whenever
C
although
D
Unless
—How long have you known the doctor ? — he helped me three years ago.
#58435
A
When
B
Before
C
Because
D
Since
Which do you prefer to use to keep in touch with your friends，QQ__________MSN?
#56400
A
and
B
but
C
or
D
so
Frank often wears a mask ________he can keep fit in the foggy and hazy (霾) weather.
#55993
A
only if
B
until
C
so that
D
even though