Question on sugars

In a displayed formula, why are the hydroxyl groups in sugars written without a dash between them? The Hydroxyl groups, carbon atoms and hydrogen atoms have dashes between each other, but the hydroxyl groups are simply written as a single unit.

Ok so the definition of displayed formula is to show all bonds between atoms

Structural formula can take many forms. It can be shown as CH3OH or it can be shown exactly the same as displayed but without the bond shown between OH when drawn.

So essentially Bond between OH shown=Displayed
Bond between OH not shown=Structural

Thanks, I think that clears it up. My book just as an error in it. That's the pain of self-studying.