Augmenter vs. accroître vs. s'accroître vs. croître

The French language offers an array of choices for expressing the idea of increase, each with its own nuance. 'Augmenter', 'accroître', 's'accroître', and 'croître' are such options that can sometimes be confusing due to their similarities. Understanding the differences can greatly improve the precision in communication.

Augmenter

'Augmenter' is a commonly used transitive or intransitive verb meaning to increase in size, quantity, or intensity.
Les charges de la compagnie ont augmenté.
(The company's expenses have increased.)
Il faut augmenter la production pour satisfaire la demande.
(It is necessary to increase production to meet demand.)

Accroître

'Accroître' is slightly more formal than 'augmenter'. It is used particularly for abstract or quantitative increases and is generally transitive.
Cette décision va accroître nos chances de succès.
(This decision will increase our chances of success.)
L'entreprise cherche à accroître son chiffre d'affaires.
(The company seeks to increase its turnover.)

S'accroître

'S'accroître' is the pronominal form of 'accroître', meaning to grow or to rise, often used in a general or economic context. It emphasizes the action as happening by itself, without specifying an agent.
La population mondiale continue de s'accroître rapidement.
(The world's population continues to grow rapidly.)
Les bénéfices de l'entreprise se sont accrus au cours du dernier trimestre.
(The company's profits have increased over the last quarter.)

Croître

'Croître' carries the idea of natural growth and is often used in reference to living organisms or things having a life-like development pattern. It's less commonly used than 'augmenter'. Croître is an intransitive verb only.
Les plantes croissent plus vite au printemps.
(Plants grow faster in spring.)
Son intérêt pour la science a crû au fil des années.
(His interest in science has grown over the years.)

Summary

While 'augmenter', 'accroître', 's'accroître', and 'croître' all convey the notion of increase, they differ in usage, context, and nuance. 'Augmenter' is versatile and common, appropriate for many everyday contexts involving increases; 'accroître' carries a more formal tone, often related to abstract or numerical growth; 's'accroître' emphasizes self-driven growth typically seen in populations or economies; while 'croître' denotes natural or inherent growth, frequently related to living beings or personal attributes such as interest or knowledge. Understanding these subtleties can greatly enhance one's expressing capabilities in French.