More slowly VS slower

Today, I was asked what is the difference between:

more slowly | slower

-> adverb | adjective

i.e. You can't use the adjective "slower" as an adverb.

For a full discussion on this point, read here.

Therefore, we must say: "Speak more slowly".

We shouldn't say "Speak slower", because Speak is a verb here, not a noun.

So, before using "slower", think: is it referring to a noun or a verb?

eg.
Speak more slowly. <--- verb/adverb!!!!
You speech should be slower. <--- noun/adjective!!!!

So, if it's an adverb (ie usually -ly), we don't change it to -ier. We use "more -ly" :)

Got it?

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