Complex sentence: Tenth Air Force immediately began attacks on Japanese airfields (Myitkyina was attacked 14 times before the end of the year) but ICW moved its route to Kunming even farther north and only two more C-46s were shot down during the remainder of 1943.
Split into simpler sentences: Tenth Air Force immediately began attacks on Japanese airfields (Myitkyina was attacked 14 times before the end of the year) and ICW moved its route to Kunming even farther north. Only two more C-46s were shot down during the remainder of 1943.