Questions & Answers about Je crois qu'il s'est fait piéger.
How does s'est fait piéger translate to "got trapped"?
The structure se faire followed by an infinitive verb (like piéger, meaning "to trap") expresses that something happened to someone, often outside of their control. It is the natural French equivalent of the English "to get [done]" or "to have oneself [done]." Here, il s'est fait piéger expresses "he got himself trapped."
Why is the helping verb est used here instead of a?
Because the verb is reflexive in this sentence! Even though faire normally uses avoir in the passé composé, the reflexive pronoun s' (se) changes the rules. In French, all reflexive verbs must use être as their helping verb in compound past tenses.
If the subject was feminine, like elle, would fait change to faite?
No, it remains exactly the same: elle s'est fait piéger. There is a special rule for this construction: when the past participle fait is followed immediately by an infinitive verb, it is invariable. It never adds an "e" or an "s" to match the subject.
Could I use the regular passive voice and say il a été piégé instead?