Z=10 points, I=1 point, G=2 points, blank (substitute for Z)=0,
A=1 point, G=2 points.
By adding the assigned value of each tiles, the total score is
sixteen (16) points when spread on non-premium square.
Why are there 2 tiles with no points on them in Words With Friends?
They are blank tiles, you can choose any letter for them however
they have no point value. Once you designate the letter to the tile
it cannot be changed, exactly like Scrabble.
The word retreating has a scrabble
point value of 11 points. The letter G has a value of 2 points. The
other letters in retreating have a value of 1 point each.