I was out of town at the time, so I don’t know exactly how it _______. 
#104951
A
was happening
B
happened
C
happens
D
has happened
推荐题目
 Visitors ________ not to touch the exhibits.
#99747
A
will request
B
are requested
C
are requesting
D
request
Great as Newton was, many of his ideas _______ today and are being modified by the work of scientists of our time.
#102473
A
are to challenge
B
may be challenged
C
have been challenged
D
are challenging
—What’s that terrible noise? —The neighbors ________ for a party. 
#104750
A
have prepared
B
are preparing
C
prepare
D
will prepare
Don’t bother to look for my dictionary --- it ______ some day.
#104100
A
turns up
B
has turned up
C
will turn up
D
is going to turn up