Complex sentence: Tropical Storm 15W entered the Philippine area of responsibility on September 7, and was named Kiko by Philippine Atmospheric, Geophysical and Astronomical Services Administration (PAGASA) for Philippine warnings before it was named Khanun by the JMA.
Split into simpler sentences: Tropical Storm 15W entered the Philippine area of responsibility on September 7. It was named Kiko by Philippine Atmospheric, Geophysical and Astronomical Services Administration (PAGASA) first before being named Khanun by the JMA.