He didn't realize he had forgot his bag _____ the plane had taken off. 
#79688
A
unless
B
until
C
if
D
or
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I was about to leave _____ the telephone rang.
#31587
A
after
B
while
C
when
D
before
 Don’t lose heart _________ you fail.
#31772
A
until 
B
as if 
C
unless  
D
even though
She wasn’t very polite but ________ I helped her.
#33735
A
any way
B
anyway
C
at any way
D
in a way