Draft: We installed a GPS but also bought a collection of road maps to ensure a trouble-free cross-country trip.

Revision: To ensure a trouble-free cross-country trip, we installed a GPS but also bought a collection of road maps.

Which revision strategy was used?

Moving the infinitive phrase to the beginning of the sentence

Making a complex sentence

The infinitive phrase To ensure a trouble-free cross-country trip was moved to the beginning of the sentence.