Prepositions of means, company and purpose

In one line

avec for company and hand tools, en for material and vehicles, par for the agent, pour for purpose, and sans for the absence of any of them.

The table

English covers most of this table with two words, "with" and "by", and that is where the trouble starts. English says "with my brother", "with a knife", "with the train", "written by Hugo", "by train". French splits them: company and hand tools take avec; vehicles take en; the agent of a passive takes par. So "with" is not a reliable signal — decide from the relationship, not the English word.

grâce à versus à cause de

Both translate as "because of", and their tone is opposite:

This distinction earns marks in exams.

English has the same pair — "thanks to" and "because of" — but treats it as optional. English will happily say "because of you I passed"; French will not. grâce à for good outcomes, à cause de for bad ones, and the choice is not stylistic.

en for material — and its rival de

Both are correct; en dominates in speech.

Note that English uses no preposition at all here — "a wooden table", "a gold watch" — turning the material into an adjective or a compound. French needs en plus the noun.

par — four jobs

par is central to the passive — the detail is in passif.

All four map onto English "by" — by Hugo, in by the window, by phone, twice a week (per). This is the one preposition where the English instinct is reliable.

pour — purpose, and its rival à

The rule: pour is the purpose of an action, à is the function of an object.

And pour has three other uses:

sans — and what follows it

No article follows sans:

And with a verb it takes an infinitive — with no de:

Il est parti sans dire au revoir. — he left without saying goodbye

English uses "-ing" after "without" and French uses the infinitive: "without saying" becomes sans dire, an infinitive. Never sans disant.

sans is negative in itself, so it needs no ne: ❌ sans ne rien dire ✅ sans rien dire. English behaves the same way — "without saying anything", not "without not saying anything".

avec — and where it must not go

avec is right for company and for hand-held tools:

But it is wrong for vehicles:

In colloquial speech avec la voiture is heard, but an exam expects en voiture.

Examples

Common mistakes

Why so many prepositions for one idea