Weak Bids
If you have <10 HCP but have a long (6+) card suit, you may be able to open the bidding with a preemptive bid.
2H, 2S ; 6-10 HCP, 6+ cards in suit, 2 of top 5 honors.
This is the standard weak 2 bid of Standard American. It is semi-constructive and somewhat disciplined. Opener is not expected to bid again unless requested to by responder. Some players will rebid their suit with a 7 card suit but in my opinion that is a mistake. If the suit was good enough to rebid then the hand was probably good enough to open at the 1 level. Opener has already accomplished two things: described hand to partner and deprived opponents of bidding space.
Some players avoid opening a weak 2 if they have 4+ cards in the other major for fear of missing a fit and a game bid in that other major.
Responder normally passes the preemptive bid unless Responder is strong and wants to try for game, or is weak also and raises the preempt to interfere with the opponents.
If Responder is strong or for other reasons thinks game may be possible, then Responder bids 2NT as a forcing bid, asking opener to indicate if opener has 8-10 HCP and a side A or K, or not. Opener rebids opener’s suit at the 3 level if either of the two conditions is not satisfied. Otherwise opener bids the side suit containing the A or K.
3H, 3S: <6 HCP, 7+ cards in suit
This is strictly a preemptive bid meant to interfere with opponents. Occasionally partner is the one interfered with. Opener does not bid again. If opener has 7+ cards in the suit and 6+ HCP, opener should open 2 of the suit.
3C, 3D: <11 HCP, 7+ cards in suit
This is strictly a preemptive bid. With a long minor suit but less than an opening hand, opener’s partnership is unlikely to find a game bid. So the effort is placed on interfering with opponents. Responder may raise the preempt if weak, or gamble on a game in the minor or NT if strong.
