ad.
1.
Really, verily, in truth, with truth, in fact, in deed, actually.
2.
Truthfully, veraciously.
3.
Honestly, candidly, plainly, sincerely, really, faithfully, in good earnest, in sober earnest, sooth to say, without equivocation, in plain English, without mincing the matter.
4.
Faithfully, constantly, steadfastly, sincerely.
5.
Correctly, exactly, strictly, accurately, justly, precisely.