Questions & Answers about Je suis content que le remplaçant soit arrivé.
Why is it soit arrivé and not ait arrivé?
In the past subjunctive, you form the verb using the present subjunctive of the auxiliary (avoir or être) plus the past participle. Just like in the passé composé, the verb arriver requires être as its auxiliary. The present subjunctive of être for the third-person singular is soit.
Why do we need the subjunctive here at all?
The phrase Je suis content que expresses an emotion. In French, expressions of emotion or feeling followed by que require the subjunctive mood in the dependent clause.
Why use the past subjunctive (soit arrivé) instead of the present subjunctive (arrive)?
We use the past subjunctive because the action in the dependent clause (the replacement arriving) happened before the feeling in the main clause (being happy). You are expressing a current emotion about something that has already occurred.
Does le remplaçant change if the replacement is a woman?