We were about to leave the classroom _____ it began to rain.
#94729
A
while
B
when
C
as
D
before
推荐题目
This is ___that they all want to but it.
#94617
A
a so useful book
B
such an useful book
C
a such useful book
D
so useful a book
______ a pair of compasses, it is easy to describe a circle.
#93189
A
Having
B
To have had
C
If you have
D
If having