Complex sentence: Hyundai Motor America began selling cars in the USA on 20 February 1986, with a single model, the Hyundai Excel, which was offered in a variety of trims and body styles.
Split into simpler sentences: Hyundai Motor America began selling cars in the USA on 20 February 1986, with a single model, the Hyundai Excel. The Excel was offered in a variety of trims and body styles.