An example of the subjunctive mood in English, which is used when talking about things that are being offered as hypothetical (such as "If I were you, then...") or things that are being hoped or demanded to happen--I think the highfalutin' term is mandative--"they asked that Smith refrain from smoking in the nursery".
I put it forward as an example of the subjunctive mood being alive and well, to the naysayers who want to claim otherwise. I think most people would call "If I were you" more correct than "If I was you" even if they couldn't explain why. I also really doubt anyone would say "they asked that Smith refrains from smoking in the nursery".
Where the subjunctive is dead, however, appears to be in most pre-high-school English classes. :(