Complex sentence: The first generation of the Ford Thunderbird is a two-seat convertible produced by Ford for the 1955 to 1957 model year, the first 2-seat Ford since 1938.
Split into simpler sentences: The first generation of the Ford Thunderbird is a two-seat convertible that was produced by Ford for the 1955 to 1957 model years. The Thunderbird was the first 2-seat Ford since 1938.