Gentler is the comparative form of gentle.
Here are some sentences that us the word gentler. The word will be in bold and italics.The little girl was gentler than a lamb.How gentler could she get?Why do you want to see the word gentler used in a sentence?Is the word gentler important to you?
part of speech
The part of speech for this particular word is a noun.
adverb
what part of speech is work
what part of speech is beneath
Either, although "gentler" seems to be more often used.
the part of speech sashay is a averb
Did is a verb, and not is an adverb. Didn't is not any part of speech. It's a contraction of did and not.
Adjective
The word speech is a noun.