Complex sentence: Melchor Palmeiro (born 1923) represented Argentina at the 1948 Summer Olympics in London, he was entered in the 1500 m, he finished fifth in his heat recording a time of 4:01.6 and failed to advance.
Split into simpler sentences: Melchor Palmeiro (born 1923) represented Argentina at the 1948 Summer Olympics in London. He was entered in the 1500 m, where he finished fifth in his heat recording a time of 4:01.6 and failed to advance.