How the fire in the dancing hall started _________ a mystery.
#100979
A
to remain
B
remains
C
is remaining
D
is remained
推荐题目
They are living with their parents for the moment because their own house ____.
#102163
A
is being rebuilt
B
has been rebuilt
C
is rebuilt
D
has rebuilt
With more forests being destroyed, huge quantities of good earth      each year.
#102348
A
is washing away
B
is being washed away
C
are washing away
D
are being washed away