A.have found out, from polluting |
B.have found, from being polluted |
C.have been found out, from being polluted |
D.have been found, from being polluted |
A.you will have to | B.one must |
C.they will have to | D.he has to |
A.lived | B.live | C.had lived | D.will live |
A.should wipe out | B.wiped out | C.be wiped out | D.had wiped out |
A.had introduced | B.are introducing |
C.have introduced | D.introduce |
A.are working | B.had worked | C.worked | D.had been working |
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