Great song by inimitable Frank Sinatra! Sinatra's recording of this song won him the Grammy Award for the best male vocal and Grammy Award of Record of the Year. Music for this song is played by Nelson Riddle and his orchestra.
P.Diddy ia an american singer, so it's Am. English. It's rather difficult to understand the meaning because of pronunciations. But in general it's very nice song, without "dirty language". There are some useful phrases. And in this song "real" English, American people say like here in the song.
There are very good example with modal verbs could (can in the Past), should