How do you say 'more than' in French?

Plus + adjective + que. 'Marie est plus grande que Pierre' (Marie is taller than Pierre). 'Ce livre est plus interessant que l'autre' (This book is more interesting than the other). The adjective still has to agree with the subject in gender and number ('elle est plus grande' uses the feminine form). For 'less than', swap plus for moins; for 'as ... as', use aussi ... que.

What is the difference between meilleur and mieux in French?

Meilleur is the adjective ('better'), used with nouns - 'un meilleur livre' (a better book), 'une meilleure idee' (a better idea), 'les meilleurs etudiants' (the best students). Mieux is the adverb ('better' as in 'more skilfully'), used with verbs - 'elle parle mieux que moi' (she speaks better than me), 'je vais mieux' (I'm doing better). Same word in English, two words in French. Same split applies to 'best': the best (adjective) is le meilleur / la meilleure, the best (adverb) is le mieux.

French Comparatives

The comparative structure is a sandwich: a marker word (plus, moins, aussi) before the adjective, que after. The adjective still agrees with the noun.

The three markers

Marker	Meaning	Example
plus	more	plus grand que (taller than)
moins	less	moins cher que (less expensive than)
aussi	as	aussi grand que (as tall as)

Marie est plus grande que Pierre. (Marie is taller than Pierre.)
Ce livre est moins interessant que l'autre. (This book is less interesting than the other.)
Le francais est aussi difficile que l'espagnol. (French is as difficult as Spanish.)

The adjective agrees with the subject (the thing being compared): plus grande because Marie is feminine.

Comparing nouns: plus de, moins de, autant de

With a noun instead of an adjective, the marker takes de and the equality marker shifts from aussi to autant.

Marker	Meaning	Example
plus de	more	plus d'argent que (more money than)
moins de	less	moins de temps que (less time than)
autant de	as much	autant d'amis que (as many friends as)

J'ai plus de livres que toi. (I have more books than you.)
Elle a moins de patience que moi. (She has less patience than me.)
Nous avons autant d'idees que vous. (We have as many ideas as you.)

The de here is the same article-collapsing de as in quantity expressions (beaucoup de pain).

Comparing verbs: plus, moins, autant

With verbs, the marker stands alone - no de needed.

Je travaille plus que toi. (I work more than you.)
Elle dort moins que moi. (She sleeps less than me.)
Il mange autant que son frere. (He eats as much as his brother.)

The three irregulars

Three French adjectives / adverbs have irregular comparative forms that don't take plus.

Word	Comparative	English
bon (adj)	meilleur	better
mauvais (adj)	pire	worse
bien (adv)	mieux	better (adverb)

meilleur agrees with the noun:

un meilleur livre (a better book)
une meilleure idee (a better idea)
les meilleurs etudiants (the best students)
les meilleures notes (the best marks)

pire has only two forms: pire (singular), pires (plural). No gender agreement.

C'est pire que je ne pensais. (It's worse than I thought.)
Les pires nouvelles. (The worst news.)

mieux is invariable - one form, no agreement.

Elle parle mieux que moi. (She speaks better than me.)
Tu vas mieux? (Are you feeling better?)
Il joue mieux au tennis maintenant. (He plays tennis better now.)

The bon / bien split mirrors English good / well: bon is the adjective, bien is the adverb. Same split for the comparatives.

You can also say plus mauvais alongside pire in many contexts - both are acceptable, with pire slightly more formal.

Superlatives (briefly)

The superlative (the most, the least) wraps the comparative in a definite article.

Marie est la plus grande de la classe. (Marie is the tallest in the class.)
C'est le livre le moins interessant. (It's the least interesting book.)
Elle parle le mieux. (She speaks the best.)

The superlative is technically Higher-tier on the AQA list. Recognise it; you don't have to produce it confidently at Foundation level.

Worked examples

Cette voiture est plus rapide que l'autre. (This car is faster than the other.)
Le francais est aussi beau que l'italien. (French is as beautiful as Italian.)
J'ai moins de temps qu'avant. (I have less time than before.)
C'est une meilleure idee. (It's a better idea.)
Tu cuisines mieux que moi. (You cook better than me.)
Aujourd'hui ca va mieux qu'hier. (Today it's going better than yesterday.)

Common mistakes English speakers make

Using plus bon instead of meilleur: ce livre est plus bon is wrong, it's ce livre est meilleur. The same goes for plus bien, which should be mieux. Forgetting the agreement on meilleur: une meilleur idee is wrong, it's une meilleure idee. And mixing up the noun and verb structures - plus de with a noun, plain plus with a verb.