The word proposal is a noun. It is something that is proposed for consideration.
The word successful is an adjective. It means to have accomplished whatever was previously proposed.
Quarantine Speech
Thomas Paine
The part of speech for "answer" is a noun.
part of speech
The part of speech for this particular word is a noun.
what part of speech is beneath
adverb
what part of speech is work
The part of speech for "unfamiliar" is an adjective.
The part of speech for "explicit" is an adjective.
The part of speech for "buried" is a verb.