A.had been pointing | B.have been pointing |
C.were pointing | D.pointed |
A.could | B.would | C.was able to | D.can |
A.didn’t see | B.haven’t seen | C.hadn’t seen | D.don’t see |
A.had done | B.would do | C.was doing | D.did |
A.sat | B.was sitting | C.have sat | D.were sitting |
A.have; polluting | B.has; polluted |
C.has; from being polluted | D.have; being polluted |
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