Complex sentence: The 323 area code was created in 1998 as yet another split of 213; after the split, 213 only covered downtown Los Angeles and its immediately adjoining neighborhoods such as Koreatown, Echo Park, and Chinatown.
Split into simpler sentences: The 323 area code was created in 1998 as yet another split of 213. After the split, 213 only covered downtown Los Angeles and its immediately adjoining neighborhoods such as Koreatown, Echo Park, and Chinatown.