"Yesterday" can be an adverb, a noun, or an adjective.
Examples
Adverb: We arrived yesterday.
Noun: Yesterday started well. All our yesterdays.
Adjective: Yesterday morning
"Yesterday" is an adverb modifying the noun "afternoon".
In the sentence "yesterday the leaves hung on the tree," "yesterday" is functioning as an adverb modifying the verb "hung."
The part of speech for this particular word is a noun.
Unbearable is an adjective. It describes something that cannot be tolerated. "Yesterday's heat was unbearable."
The part of speech for "answer" is a noun.
Yesterday is a noun in that sentence.
"Yesterday" is an adverb modifying the noun "afternoon".
The word yesterday is an adverb.
Yesterday is an adverb in that sentence.
Walked is a verb.
I think yesterday is a noun, because it is definitley not a verb or adjective. It is not an action and it does not describe anything.
It's an adverb.
In the sentence "yesterday the leaves hung on the tree," "yesterday" is functioning as an adverb modifying the verb "hung."
Yesterday he paddled his canoe out into the lake and camped on an island overnight.
She gave a terrific speech yesterday.
The part of speech for this particular word is a noun.
part of speech