I think we're on the same (a)   . (to express agreement)

Your (a)   is sound, I fully support it. (to express agreement)

There's another (a)   of the puzzle. (to question the ideas mentioned)

I'm skeptical (a)   this idea.

I find that idea to be at (a)   with knowledge I have (meaning: "I can't agree with this idea")

I am (a)   to disagree. (MEANING: "I tend to")

I see what you mean, but it's simply not the (a)   . (to express disagreement)