Thanks to Nadia of Boumerdes for this question.
What’s the difference between an adjective and an adverb? The simplest answer is to say that an adjective describes a noun, while an adverb describes a verb.
ex 1. A slow truck – adjective(slow) + noun.
ex2. The truck was moving slowly – noun + verb + adverb(slowly)
We can compare two things using either adjectives or adverbs:
ex .1 Truck A is slower than truck B
ex 2. Truck A is moving more slowly than truck B
The same principle applies to the irregular forms, and is the same for both adjective and adverb:
good/well – better, bad/badly – worse
ex 1. He speaks good English.
ex2. He speaks English very well.
ex 1. John’s English is better than Peter’s.
ex 2. Jane speaks English better than John.