widespread sources of air pollution
A. point source
B. nonpoint source
C. ozone
D. conservation

Random Topics:
Grammar - ConnectorsTenses (Present, Past, Future Forms)Modals and Phrasesmust/shouldUse of Prepositions or ConjunctionsAdverbs of TimeCity PlacesWho vs WhomGrammar / PronounsHelpful PhrasesOther quiz:
Grammar › ViewI (read)___________ the book you lent me, but I (not/ finish)_________ it yet. It’s very interesting.
A. have read/haven’t finished
B. have been reading/haven’t finished
C. have been reading/haven’t been finishing
D. have read/haven’t been finishing
Grammar › View
Choose the gerund in the sentence. Last night, we watched a fascinating show about fishing in Alaska.
A. fascinating
B. fishing
C. fishing in Alaska
D. watched a fascinating show
Adverbs, Modals, Preposition of time › ViewShe finishes her paper round ________ eight o’clock.
A. at
B. in
C. on
Grammar › View
Choose the type of sentence that describe the sentence below best:
Fall is my favorite season.
_
A. Declarative
B. Interrogative
C. Imperative
D. Exclamatory
