How are adverbs formed in French?

Adverbs in French grammar are formed in several ways:

From Adjectives:

Many adverbs are formed from adjectives by adding "-ment" to the feminine singular form of the adjective.

Example: Lent (slow) → Lentement (slowly).

From Nouns:

Some adverbs are formed from nouns by adding "-ment" to the base form of the noun.

Example: Régulier (regular) → Régulièrement (regularly).

Irregular Forms:

Some adverbs have irregular forms and do not follow a specific pattern.

Example: Bon (good) → Bien (well).

From Adjectives without Change:

Some adverbs are identical to their corresponding adjectives and do not require any change.

Example: Clair (clear) → Clair (clearly).

From Prepositions:

Some adverbs are formed from prepositions.

Example: Dehors (outside), Dedans (inside).

From Other Adverbs:

Some adverbs are formed from other adverbs by adding "-ment" to the base form.

Example: Vite (quickly) → Très vite (very quickly).

These are the main ways adverbs are formed in French, but there are exceptions and irregularities as well.