Complex sentence: In 1603 Ribera built Fort Chepe and Fort San Pedro to cover the crossing at the mouth of the Bio Bio River, rebuilt San Felipe de Araucan and Santa Margarita de Austria on the coast between the aillarehues of Arauco and Tucapel and Paicavi on the Paicavi River.
Split into simpler sentences: In 1603 Ribera built Fort Chepe and Fort San Pedro to cover the crossing at the mouth of the Bio Bio River. He rebuilt San Felipe de Araucan and Santa Margarita de Austria on the coast between the aillarehues of Arauco and Tucapel and Paicavi on the Paicavi River.