Learn Italian: Abbiamo saltato la siepe per scappare.

Verbs like saltare (to jump) use essere when they describe directed motion without a direct object (like Siamo saltati sul letto - We jumped onto the bed). However, in this sentence, saltare is used transitively because it takes a direct object (la siepe). Whenever a verb takes a direct object, its auxiliary must be avere.

If I wanted to say "we jumped over the hedge" using a preposition, how would the grammar change?

If you add a preposition like sopra (over), the verb no longer takes a direct object. It becomes an intransitive verb of directed motion, which triggers the auxiliary shift to essere. You would have to say Siamo saltati sopra la siepe.

Does saltare with a direct object always mean "to jump"?

Not always! When used transitively with avere, saltare frequently means "to skip" or "to omit" something abstract. For example, Abbiamo saltato il pranzo means "We skipped lunch." In our sentence, the context of the hedge (la siepe) tells us it means a physical jump.

Why do we use per before scappare instead of a?