One thing’s for sure, the fire _____by some cigarette butts. 
#88084
A
might cause
B
could have caused
C
must have been caused
D
should be caused
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Without your help,we       this task.
#89666
A
don’t finish
B
will not finish
C
didn’t finish
D
would not have finished
_____ my advice, you would not be in such a terrible situation now.
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A
Had you taken
B
If you take
C
Should you take
D
If you have taken
We ______the luggage for him. His brother did it for him.
#86642
A
didn’t need carry
B
needn’t have carried
C
didn’t need to carry
D
needn’t carry
 The manager demanded that the task ______ within a week.
#87298
A
must complete
B
would be completed
C
be completed
D
must be completed