Mrs Black isn’t in and I’ll have to ring ______. I would appreciate it if you ring _____ after 6 o'clock?  
#24999
A
off; back
B
up; off
C
out; up
D
back; off
推荐题目
 I won’t call you ______ something unexpected happens.
#22603
A
unless
B
whether
C
because
D
while
 There was such a long queue for coffee at the interval that we _____gave up.
#24125
A
eventually
B
unfortunately
C
generously
D
purposefully