Sometimes I work ________ the day and sometimes _________ night. 
#48953
A
on, at
B
at, on
C
at, in
D
in, at
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It’s important _________ us _________ some good friends.
#47232
A
for, having
B
of, to have
C
for, to have
D
of, having
Can you please spend _____ explaining it _____ us?
#50286
A
sometimes; to
B
some time; to
C
some times; for
D
sometime; for
Only four days remained ____ the exam.    
#50123
A
at
B
after
C
before
D
since