We can never expect ______ bluer sky unless we stop ______ industrial waste going into _____ atmosphere.
A.a; the; the | B.the; the; the | C.a; /; the | D.the; /; / |
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We can never expect ______ bluer sky unless we stop ______ industrial waste going into _____ atmosphere.
A.a; the; the | B.the; the; the | C.a; /; the | D.the; /; / |