Learn Italian: L'alpinista si è rassegnato al vento gelido. - The mountaineer resigned himself to the freezing wind.

The pronominal verb rassegnarsi (to resign oneself) strictly requires the preposition a to introduce the thing you are giving in to. Because it is followed by the masculine singular noun il vento, the preposition a combines with il to become the articulated preposition al.

How does this sentence reveal the gender of the mountaineer?

Nouns ending in -ista like alpinista use the exact same form for both masculine and feminine in the singular. We only know this mountaineer is male because the past participle rassegnato ends in -o. If the mountaineer were female, the sentence would be L'alpinista si è rassegnata.

Why is essere used as the helping verb here instead of avere?

The verb rassegnarsi uses the reflexive pronoun si. In Italian, all verbs that take a reflexive pronoun, including pronominal verbs of effort and resignation, must use essere to form compound tenses like the passato prossimo.

Is there a difference between gelido and freddo?