[ Grammar Clauses ]
Factories allow these dangerous substances to pour into the rivers, ___ their chimneys fill the atmosphere with poisonous fumes.
A. while
B. where
C. although
D. so that

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Transitive or Intransitive VerbsPresent, Past and Future TenseSubject Verb Agreement Irregular VerbGrammar and IdiomsModals and PhrasesConjunctions - ConnectorsNoun QuantifiersModal AuxiliariesVocabulary and DefinitionsTypes of Sentence StructuresOther quiz:
Grammar › ViewI ______ the accident while I______ for the bus.
A. was seeing / waited
B. saw / was waiting
C. was seeing / was waiting
D. saw / waited
Grammar › View
Are you coming to……party next Saturday?
A. a
B. an
C. the
D. X
Preposition › ViewWhat are you talking _______ ?
A. about
B. on
C. with
D. to
Grammar › View
Sinta and Jojo _____ many songs
A. Sing
B. Sings
C. Singing
D. Sang