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Types of Sentence StructureModals and InversionPassive Voice - Mixed TensesPerfect Tenses of VerbsPerfect ModalsVerb FormModal Verbs and Gender NounsLinking WordsZero Conditional Sentenceused to vs be used to vs get used toOther quiz:
Mixed General Quiz › ViewThis is very valuable. Please look ___ it.
a. at
b. for
c. after
Vocabulary › View
chemical pollution in the air mixed with falling water
A. emissions
B. smog
C. acid rain
D. sewage