Complex sentence: This led to Civil war with UNITA, which received varying degrees of support from the U.S. and South Africa in the 1980s, continued until 2002, when UNITA leader Jonas Savimbi was killed.
Split into simpler sentences: This led to civil war with UNITA, which received varying degrees of support from the U.S. and South Africa in the 1980s. The war continued until 2002, when UNITA leader Jonas Savimbi was killed.