Complex sentence: On July 10,1991, the United Nations announced plans to open a humanitarian center at Lake Hammar to care for Shia opposition hiding out in the southern marshlands, but Iraqi forces did not allow UN relief workers into the marshlands or the Shia out.
Split into simpler sentences: On July 10,1991, the United Nations announced plans to open a humanitarian center at Lake Hammar to care for Shia opposition hiding out in the southern marshlands. However, Iraqi forces did not allow UN relief workers into the marshlands or the Shia out.