Adverbs - Basic Rules
Adverbs are used together with: verbs, adjectives and other adverbs. In French, they never change their form, except the adverb 'tout'. Many adverbs end in -ment. If the adjective ends in -ant, the adverb based on the former ends in -amment.
The -ant → -amment rule also applies to -ent adjectives: -ent adjectives usually become -emment adverbs.
Some examples here would be very useful to learners who have a limited vocabulary to understand this with.