31. We should think of ways to stop the waste from the factory _____ our living environment. 
#81053
A
being polluted
B
polluting
C
from being polluted
D
Polluted
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She pretended         TV when her mother came in.
#67022
A
not to be watching
B
not watching
C
to not watch
D
having not watched
What a pity! He____________ the only chance of success.
#83347
A
threw away
B
put down
C
gave in
D
broke off