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She is in middle school and already taking higher level math courses.
He is not the most popular kid in school.

These emboldened words were labelled 'comparative and superaltive adjectives. Aren't they adverbs? Please explain. Thank you
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They are adjectives, modifying courses and kid respectively.

"level" is not an adjective, so "higher" is not an adverb

"popular" is an adjective, and "most" is the form for the superlative
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Philippopular" is an adjective, and "most" is the form for the superlative

Ah right, silly me. Thank you.
Philip"level" is not an adjective, so "higher" is not an adverb
Oh really, I thought level was an adjective... So it's a noun then?

He is one of the most Popular teacher in school

He is one of the most popular teachers in school.

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