Complex sentence: In late 1944 and early 1945 the British Indian Army first halted and then devastatingly reversed the Japanese attack on India, in which almost half the Japanese forces and fully half the participating INA contingent were killed.
Split into simpler sentences: In late 1944 and early 1945 the British Indian Army first halted and then devastatingly reversed the Japanese attack on India. Almost half the Japanese forces and fully half the participating INA contingent were killed.