adj can modify plural countable nouns or singular definite articles can modify uncountable and countable nouns
indefinite article a/ An modifies a countable noun singular
adverb (adv) modifies a verb or a verb phrase
be verb followed by an adjective or a present participle
Preposition (prep) followed by a gerund
Generally used at the beginning of a sentence, there are common be verbs, special interrogative words (how to where ...), and another imperative sentence, usually Don't ...
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