singular or plural:
I used this example in a post (The difference among "type of", "sort of", "kind of" and "style of" when referring to categories)
Adverbs are a type of words that describe verbs adjectives other adverbs or clauses.
Where I'm not sure which is supposed to be used, singular or plural. I guess each of them makes sense.
Adverb is a type of words that describe verbs adjectives other adverbs or clauses.
refers to any/each adverb;
with plural, it refers to all types of adverbs.
Is my understanding right?