The word either can be an adjective. Another word to use is whichever.
Either is not an adjective. It has no degrees.
The word constant can be used as either a noun or an adjective, to describe something that is essentially unchanging.
NO because contribute can either be a noun or verb.
Depending on how it is used a number can be either a verb or an adjective.
The word "hard" can be either an adjective or an adverb. E.g. Concrete is hard. It was a hard test. (adjective) He works hard at his job. Push hard on the button. (adverb)
It can either be a verb or a adjective.
No, cough is not an adjective. It can be either a noun or a verb.
It can be either an adjective or a noun depends on the meaning.
Either is not an adjective. It has no degrees.
It depends on how it is used. It can be either a noun or an adjective.
It is either an adjective (intelligent, stylish) or a verb (to hurt or ache).
Yes, it can be either an adjective or an adverb, meaning near, close by.
The word these can be a pronoun or an adjective. In either use, it is the plural form of this.
The word "for" is not an adjective of any kind. It is either a preposition or a conjunction.
The word "when" is never an adjective. It is either an adverb, conjunction, noun, or pronoun.
Coming can be either an adjective ("this coming Thursday") or a noun ("the coming of spring").
No. Highlight is either a verb or a noun. The past participle highlighted can be an adjective.