French Grammar Guide: The Rules That Trip Learners Up

Use the passé composé for completed, one-time past actions ("j'ai mangé" — I ate / I have eaten) and the imparfait for ongoing, habitual, or descriptive past states ("je mangeais" — I was eating / I used to eat). In a story, the imparfait sets the background ("il faisait beau") and the passé composé carries the events that move it forward ("soudain, il a commencé à pleuvoir").

The most common mistake is using the passé composé for a description or a habit. "Quand j'étais enfant, je jouais au foot" (a habit → imparfait), not "j'ai joué" unless you mean one specific occasion.

With être, the past participle agrees with the subject in gender and number: "elle est allée", "ils sont partis". With avoir, it does not agree with the subject — but it agrees with a direct object that comes before the verb: "les pommes que j'ai mangées" (mangées agrees with "les pommes"). With no preceding direct object, there is no agreement: "j'ai mangé des pommes".

This is one of the highest-value rules for written French — a reader or examiner notices a missing agreement immediately.

A direct object (COD) answers "qui ? / quoi ?" and is replaced by le, la, les: "Je vois Marie → je la vois". An indirect object (COI), usually introduced by "à", answers "à qui ?" and is replaced by lui, leur: "Je parle à Marie → je lui parle". The pronoun goes before the verb: "je lui parle", "je ne la vois pas".

Mixing the two ("je le parle" instead of "je lui parle") is a frequent error that a listener or reader catches instantly.

French subject pronouns are je, tu, il/elle/on, nous, vous, ils/elles, and the verb agrees with the subject. "On" (informal "we" or "people") takes the il/elle form: "on mange". "Vous" is both the plural and the formal singular, and always takes the plural form: "vous avez".

Connectors structure your ideas: "et" (and), "mais" (but), "donc" (so), "car" / "parce que" (because), "cependant" (however). In a simple list, "et" is not preceded by a comma ("A, B et C"), and there is no liaison after "et" — the final "t" is silent. Varying your connectors beyond "et" and "mais" raises the perceived range of your French.

Write and speak under exam-style conditions, then get feedback that flags the exact error and explains the rule. Langujet's feedback on French-exam tasks (TEF, TCF, DELF, DALF) highlights grammar slips — tense, agreement, pronouns — sentence by sentence, so you fix your own recurring patterns instead of re-reading grammar books.