They ___________ for two hours 
#102329
A
is working
B
worked
C
have been working
D
had worked
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– Your job ________ open for your return.– Thanks.
#104588
A
will be kept
B
will keep
C
had kept
D
had been kept
 I ______ this book for two weeks. I have to return it now.
#101638
A
have borrowed
B
have kept
C
have lent
D
have returned
It is reported that very little use of these waste materials_______ in the past decades.
#99386
A
was taken
B
was made
C
has been made
D
has been taken