"Which is in a more imperative tone?" Is the correct question. It's example one: "you had better..." Both actually sound like veiled threats, but I suppose the context would make the meaning clearer.

Peachey has advised you well on the subject. I would add that there are subtle nuances or distinctions in language such that we all have our own "best feeling" about how a sentence should sound, or feel when we word it. Remember Shunsuke, that English can be very flexible. My preference in the wording would be something like this. "The more imperative tone would be.......etc." --------------------------- Which is in more imperative tone? (This is okay) Which is in more an imperative tone? (This should be; "Which is in A more imperative tone?") Which is in more imperative a tone? (Not really sure, but this feels to me like a very awkward wording, and I would not ever use it. There is a rhythm in English that native speakers learn as children, and the A would not normally be placed that late in a sentence by Native Speakers in the USA) --------------------------

1, You had better do〜 <-- normal and usual 2, It would be to your advantage that 〜 <-- too "high style" --> Which one is more imperative?

I agree with Peachey that the two constructions both sound a bit like veiled threats, certainly if the context is "giving advice to someone." Why not use something like: "You absolutely must ..." "It's absolutely imperative that you ... " Maybe even "It's a non-negotiable requirement of your job that you." To me, this removes all notion of an implicit threat, because it removes the well-being of the addressed person out of the sentence. It just tell the other like it is; that something is required of them. It could also be that you would want to warn someone about a potential threat coming from outside, out of your control. Well then I'd be friendly and just be somewhat more explicit. Just tell them that you think his superior (or teacher, whatever) is nog going to be happy with the addressed person and might fire him on the spot or so. Native speakers, please comment if you see room for improvement.