Strong openings
2

1) 23+ HCP balanced or semibalanced
2) major-onesuiter with 8.5+ playing tricks
3) minor-onesuiter with 9.5+ playing tricks

4) 2-suiters should be opened with 1 of a suit except you can give a 100% guarantee for game. It is very difficult to show both suits after 2.
2NT 20-22 HCP balanced or sometimes also
semibalanced (if there stopper in the short suits.)
4 Solid s; 8.5 - 9 playing tricks; at least 1 A outside.
Answers: accept, cuebid or RKCB
4 Solid s; 8.5 - 9 playing tricks; at least 1 A outside.
Answers: accept, cuebid or RKCB
4NT

ACOL asking for Aces (For very special monster-hands)
E.g. AKQJ10xxx, - , KQJ10, A

Answers:
5 = noA;
5 = A; 5 = A; 5 = A; 6 = A;
5NT = 2 Aces