It's an adverb.
The word yesterday is an adverb.
Did and attend are verbs, and not is an adverb.
In the sentence, "Which is his sister?", "which" is an interrogative pronoun.
Why is the beginning of a interrogative sentence.
Noun--however, many words have several possible parts of speech; please submit the Whole Sentence when asking for part of speech--cannot be sure without seeing how it is used in the sentence, as that's what determines the part of speech.
Yesterday is a noun in that sentence.
Yesterday is an adverb in that sentence.
In the sentence "yesterday the leaves hung on the tree," "yesterday" is functioning as an adverb modifying the verb "hung."
She gave a terrific speech yesterday.
Practice is a noun in that sentence. It's the object of the preposition "for".
Verb
Where did you attend college? (You did attend college where?)where - adverb, modifies the verb 'did attend';did - auxiliary verb;you - personal pronoun, subject of the sentence;attend - main verb;college - noun, direct object of the verb 'did attend'.
What college did he attend? (He did attend what college?)what - interrogative pronoun, functioning as a determiner;college - noun, direct object of the verb 'did attend';did - auxiliary verb;he - personal pronoun, subject of the sentence;attend - main verb.
The word yesterday is an adverb.
"Yesterday" is an adverb modifying the noun "afternoon".
Did and attend are verbs, and not is an adverb.
The words 'Yesterday Nick visited and old village' is NOT a grammatically correct sentence for two reasons. First, the word 'and' is a connecting word to make a compound subject, compound verb, or compound sentence. Instead of 'and' in your sentence, you need one of three words: a, an, or the. Those three words are called articles of speech and come before nouns. Second, you need a comma after Yesterday. Note: you use 'an' before words beginning with a vowel.So the sentence should read:Yesterday, Nick visited an old village. (or the old village)Yesterday is an adverb.Nick is the nounan old village is the object phrasean is an articleold is an adjective modifying villagevillage is the object.You can also write the sentence: Nick visited an old village yesterday.