5 French Conjugation Mistakes to Avoid (and How to Fix Them)

3 min read

French conjugation can feel like an obstacle course: silent endings, picky auxiliaries, irregular stems. It is easy to trip.

Here is the useful secret: most learners stumble on the same handful of patterns. Spot these traps early and you save months of guesswork. Below are the five most frequent mistakes—and how to stop making them.

Written by Nathan — native French speaker, specializing in teaching French.

1. The Silent Endings Trap (-e, -es, -ent)

This is the number-one issue in spoken French: many endings are spelled differently but sound the same—or disappear entirely.

Silent endings on -er verbs (present)

Wrong:Pronouncing -ent in ils mangent like the word “enfant,” or adding extra syllables for je mange / tu manges.

Correct:For -er verbs in the present, -e, -es, -e, and -ent are fully silent after the stem. Je mange, tu manges, ils mangent all rhyme on mange.

Why this happens:Written French keeps more letters than speech; learners often “read aloud” endings that native speakers drop.

The fix:Train your ear first: listen, then repeat short lines without exaggerating the last letters. Picture the word stopping at the stem vowel until the habit sticks.

2. Mixing Up Être and Avoir in the Passé Composé

French uses two auxiliaries in the compound past. If you default to avoir every time, movement and pronominal verbs will stay wrong.

Wrong auxiliary with movement verbs

Wrong:J’ai allé au marché.

Correct:Je suis allé au marché. (agreement rules apply with être)

Why this happens:Most verbs take avoir, but a core set of movement and change-of-state verbs—and all pronominal verbs (se laver, se souvenir)—use être.

The fix:Memorize DR & MRS VANDERTRAMP (or your teacher’s short list) for classic être-auxiliary verbs, then drill aller, venir, naître, mourir, rester until the pattern feels automatic.

Practice French conjugation for free in the Croissant Verbs app

Quizzes and spaced repetition for every tense, for free on your phone—plus short grammar guides on our Learn hub.

3. Forgetting Past Participle Agreement With Être

Agreement with être trips up learners—and plenty of native speakers in writing. The rule itself is consistent once you see it.

Gender and number on the past participle

Wrong:Elle est parti.

Correct:Elle est partie.

Why this happens:With auxiliary être, the past participle agrees in gender and number with the subject.

The fix:Quick check: if the subject is feminine and/or plural, add -e, -s, or -es as needed—Elles sont allées. Spend one week on agreement-only mini-drills if this is your weak spot.

4. Confusing the Passé Composé and the Imparfait

At intermediate level, this is the big split: the two past tenses are not interchangeable—they do different jobs in a story.

Passé composé vs imparfait at a glance
Tense	Typical use	Example
Passé composé	A completed action; something that happened (often once) and moves the plot.	J’ai mangé un croissant.
Imparfait	Habit, background, description, or an ongoing scene.	Je mangeais un croissant chaque matin.

Rule of thumb: if English could be “I used to …” or “I was …-ing,” lean toward imparfait. If it is a single completed bump in the narrative, lean toward passé composé.

5. Stem Changes (“Boot” Verbs)

Some verbs swap their stem for certain persons—when you chart them, the irregular forms can look like a boot shape around the edges.

Broken nous / vous forms

Wrong:Nous manges or vous devent.

Correct:Nous mangeons / vous devez.

Why this happens:Verbs like devoir, boire, or prendre often use a different stem for nous and vous than for je, tu, il/elle/on.

The fix:Overload practice on nous and vous for each new irregular verb; they are usually where the “regular-looking” pattern breaks.

How to Put Conjugation on Autopilot

Knowing the rules is step one; retrieval under pressure is what speaking requires. Stack these habits:

Record yourself: say a short story, listen back, and flag endings you exaggerated or skipped.
Target one weak spot: if agreement is the leak, spend ten minutes a day for a week on être + participle drills only.
Use full sentences: do not only conjugate manger—say Je mange une pomme. Context beats word lists for memory.
Need a nudge? Use the interactive practice hub to catch these patterns and fix them in real time.

Most accuracy gains come from repeating the same corrections until they feel boring. Pick one mistake type from this list, drill it for a week, then rotate.

Open the practice hub →