I was about to go to bed _____ someone knocked at the door.
#71475
A
when
B
then
C
at the time
D
and
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 It’s not until no enemies were left that they________ . 
#72174
A
did not stop fighting
B
did stop fighting
C
stopped fighting
D
have stopped fighting
The hill ____ is covered with tress is called Huang Hill.
#68719
A
of which top
B
whose the top
C
whose top
D
top which