Accord du participe passé suivi d'un infinitif

This grammar is all about who is doing the work. In French, we usually agree the past participle with the object. This happens if the object comes before the verb. But the infinitive changes the game. The infinitive is the second verb in its er, ir, or re form. Think of the past participle as a mirror. It wants to reflect the gender and number of the object. But the infinitive acts like a shield. It only lets the agreement through if a specific condition is met. You must ask one simple question. Is the object the one performing the action of the second verb? If the answer is yes, you agree. If the answer is no, you stay neutral. It is like a job interview for words. Only the ones doing the work get the agreement. It is a very logical system once you see the pattern. You are just tracking the "actor" in the sentence.

1. 1Start with your subject and the auxiliary verb avoir.
2. 2Add the past participle of a perception verb like voir or entendre.
3. 3Place your direct object before these verbs. This is usually a pronoun like les or que.
4. 4Follow immediately with an infinitive verb.
5. 5Check if the direct object performs the action of the infinitive.
6. 6Add e, s, or es to the past participle only if the object acts.
7. 7Leave the past participle in its masculine singular form if the object is acted upon.

You use this pattern when you describe something you saw or heard happening. Imagine you are at a busy French cafe. You see a famous actress walking by. You want to tell your friend. You say: L'actrice que j'ai vue passer. Why the e on vue? Because the actress is the one doing the "passing." She is the star of the second verb. Use this when you are reporting events. It works great for job interviews too. You might say: Les projets que j'ai vus réussir. The projects were the things succeeding. It makes your French sound very polished and precise. Use it when you want to be clear about who did what. It is very common with verbs of the senses. Entendre, voir, sentir, and regarder are your best friends here. They help you paint a picture of a scene. You are basically a director setting the stage with your words.

You skip the agreement when the object is the "victim" of the action. This sounds dramatic, but it is just grammar. Imagine you hear a song being sung in a metro station. The song is not singing itself. Someone else is singing the song. In French, you say: La chanson que j'ai entendu chanter. Note that entendu has no extra e. The song is the object of the singing, not the singer. This is a very common trap. Also, there is a special rule for the verb faire. When fait is followed by an infinitive, it NEVER agrees. Ever. Not even if the object is doing the work. For example: Je les ai fait rire. Even if les is feminine plural, fait stays the same. Think of fait as a stubborn person who refuses to change clothes. It is a fixed block. This also applies to laisser in modern rules, though some people still agree it. To stay safe and modern, keep fait and laisser simple and unchanged.

The biggest mistake is agreeing by reflex. Many people see a feminine object and immediately add an e. They write La pièce que j'ai vue jouer. But the play doesn't play itself! Actors play the play. So, it should be La pièce que j'ai entendu jouer. Yes, even native speakers mess this up sometimes. It is the "over-agreement" trap. Don't be too eager to add letters. Another mistake is forgetting the faire rule. You might want to write faites because you are talking about girls. Resist the urge! Fait stays fait. Think of it like a grammar seatbelt. It keeps your sentence from crashing. Finally, people often mix up the position. The object must be before the verb for any of this to matter. If the object is after, there is no agreement anyway. It is like trying to use a coupon after you already paid. It just doesn't work that way.

How is this different from normal past participle agreement? Usually, with avoir, you just look at the direct object. La pomme que j'ai mangée. Easy, right? The apple is eaten. But the infinitive adds a second layer of logic. It's like moving from 2D to 3D. In the normal pattern, the object is just a target. In this pattern, the object can be an actor. Another contrast is with the verb être. With être, you always agree with the subject. Elle est sortie. This rule only applies to the avoir team. Don't mix the two teams up. It is like mixing salt and sugar. Both are useful, but they serve different purposes. This rule is more specific and requires more thought. It is the difference between a quick snack and a gourmet meal. Take your time to digest the logic. You will see it everywhere once you know it.