Complex sentence: The carriers launched attacks against Jaluit and Mili atolls, Marshall Islands, on 19 November, to neutralize enemy airfields there; then provided air support for the amphibious landings on Makin and Tarawa, Gilbert Islands.
Split into simpler sentences: The carriers launched attacks against Jaluit and Mili atolls, Marshall Islands, on 19 November, to neutralize enemy airfields there. The force then provided air support for the amphibious landings on Makin and Tarawa, Gilbert Islands.