#1
Hey sup guys. Trying to play a song but it has quite a bit of string bending. I understand when its asks for a half bend or a full bend. But what about 1 1/2 or something like -3? I was just like WTF? How do you bend a string -3?

Also it kind of asks for a couple of harmonics here and there. A regular harmonic and one marked A.H.? What type of harmonic is A.H.?

Okay thanks!
#2
Well a 1 1/2 is a full bend plus one step, for example if you play the G(3rd fret) on the high E a 1 1/2 bend you would bend that G to a pitch of A#(6th fret), which is possible. As for the -3 or even if it was a +3 that is a tremelo bar usage. -3 you would push down on the bar lowering the pitch by 3 steps, for example lowering that newly made A# down to an E(open string). Its just the opposite for +3(assuming you have a floating tremelo) you jsut raise that open E back up to A#. Hope taht made sense.
#4
Yea AH is artificial harmonics. I believe there are various ways to do this but the most common is pinch harmonics. If you don't know, vaguely its hitting a harmonic beyond the fretboard by letting your thumb hit the string right after your pick doesn, essentially "pinching" it.