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phrasal – adj. grammar: of, relating to, or consisting of a phrase or phrases
unit -- n. a single thing, person, or group that is a part of something larger
expletive – n. a word or phrase that fills out (or takes a slot) in a sentence without adding to the meaning
conversation – n. a talk involving two people or a small group of people
practice – v. to do something again and again in order to become better at it
