Complex sentence: Those who came to Aman became known as the Falmari or "sea elves" and these are the Elves who are generally known as Teleri, though the term also includes their Middle-earth cousins the Sindar, Laiquendi, and Nandor of Middle-earth.
Split into simpler sentences: Those who came to Aman became known as the Falmari or "sea elves". The Teleri were the ancestors of the Valinórean Teleri, and the Sindar, Laiquendi, and Nandor of Middle-earth.