Complex sentence: Area code 917 is a New York City telephone area code; it is the standard cellular/pager/voicemail phone area code for all of the city's boroughs and is an overlay to 212,347,646 and 718.
Split into simpler sentences: Area code 917 is a New York City telephone area code. It is the standard cellular/pager/voicemail phone area code for all of the city's boroughs and is an overlay to 212,347,646 and 718.