Complex sentence: He did manage to have contact with many people he knew from when he lived there in high school, and he was able to see even more of the country, and learn a lot more about the Japanese people, as well as learn the Japanese language.
Split into simpler sentences: He did manage to have contact with many people he knew from when he lived there in high school. Trevor was able to see even more of the country, and learn a lot more about the Japanese people, as well as learn the Japanese language.