Breakdown of Elle m'a téléphoné pour s'excuser.
elle
she
pour
for
avoir
to have
téléphoner
to call / to phone
Questions & Answers about Elle m'a téléphoné pour s'excuser.
Why is m' an indirect object here? In English, we just say "she called me".
Where exactly does the object pronoun go in the passé composé?
Object pronouns always go immediately before the conjugated verb. In the passé composé, the conjugated verb is the helper verb (here, a from avoir). So, me goes right before a, which then shrinks into m'a because of the vowel. It never goes right before the past participle (téléphoné).
If a woman is speaking, shouldn't téléphoné get an extra "e" at the end?
No, it stays exactly as it is! In the passé composé, you only make the past participle match a preceding direct object. Because m' is an indirect object (thanks to téléphoner à), téléphoné does not change, no matter who is speaking.
Why do we use pour before s'excuser?
When you want to say "in order to" do something in French, you use pour followed by the infinitive (the unconjugated dictionary form) of the verb. So pour s'excuser literally means "in order to apologize."