Since the time humankind started gardening, we _____to make our environment more beautiful.
#99086
A
try
B
have been trying
C
are trying
D
will try
推荐题目
He ______________ two tickets for us before he arrived at the entrance of the cinema. 
#99545
A
had reserved
B
has reserved
C
was reserving
D
has been reserving
I ______ him in time, otherwise he would have fallen off the bike.
#103285
A
had supported
B
supported
C
have supported
D
support
  I don’t think Jim saw me ; he ______ into space .
#104041
A
just stared
B
was just staring
C
has just stared
D
had just stared
"The moment _____soon," he thought to himself, waiting nervously.
#102148
A
came
B
has tome
C
was coming
D
is coming