Complex sentence: He defeated Melvin Manhoef at Dream 15, in the Light Heavyweight Grand Prix semifinal, in the final he fought with Gegard Mousasi, and lost to him by rear naked choke.
Split into simpler sentences: He defeated Melvin Manhoef at Dream 15, in the Light Heavyweight Grand Prix semifinal. In the final he fought with Gegard Mousasi, and lost to him by rear naked choke.