Learn French: Grâce à sa persévérance, il a fini par sortir du dédale. - Thanks to his perseverance, he ended up getting out of the maze.

The construction finir par followed by an infinitive (here, sortir) is the standard way to express "to end up doing [something]" or "to finally do [something]". In this sentence, it is conjugated in the passé composé (il a fini) to show the ultimate result of his past actions.

Could I use à cause de instead of grâce à to say "because of his perseverance"?

No, because grâce à is specifically used for positive causes (literally "thanks to"). À cause de means "because of" but carries a negative or blame-oriented tone. Since his perseverance is a good trait that led to his escape, grâce à is required.

Why is it sortir du dédale rather than just sortir le dédale?

When the verb sortir means "to exit" or "to go out of" a physical place, it must be followed by the preposition de. In this sentence, de combines with the masculine definite article le to form the mandatory contraction du.

Since the subject is il (he), why do we use the feminine possessive sa persévérance?