Responding to major suit openings

Walter has three spades, so with Penelope showing 5 when she opens 1S, he knows they have a major suit fit. He only has 8 points, a weak hand, so he should just raise spades by one level to 2S.

Walter has a weak hand with no fit. The only suit that there is room to bid at the one level is spades and he would need four of them to do that. He does have enough points to respond, though (6+), so he should bid 1NT.

Again, Walter has a weak hand with no fit. This time, though, there is a suit that he can bid at the one level. Remember that as responder, you only need four cards in a major suit to bid it, so here Walter can bid 1S. Because he is responding at the one level, he is only showing responding strength - at least 6 points.

Note: If you respond 1NT when there is room for you to have shown a major suit at the one level, your partner will assume you don't have four or more cards in a major, because you should always show a major suit of 4+ cards when you have one.

Walter has 11 points, which might be enough for game if Penelope is not minimum for her bid, so his hand is invitational. He can show both the fit and his invitational strength by bidding 3S, then Penelope can pass when her hand is minimum or bid 4S when she has a bit extra.

Here again, Walter has an invitational hand - 11 points, but this time he has no fit with partner's suit. He can't show his nice club suit because that would mean responding at the 2 level, which would show a game forcing hand. He doesn't have four or more spades (he could bid 1S if he had), so he must bid 1NT for now and see what his partner does next. If Penelope makes another bid, he will be able to show his invitational strength with his next bid.

Walter has a good hand here. He has fit with partner's suit and he has 14 points - a game forcing hand. He can show both the fit and his strength by bidding game straight away. 2s would show a weak hand with fit and 3S would show an invitational hand with fit, so he is too good for either of those.

Walter doesn't have fit with partner's spades but he does have a game forcing hand so he can show his own suit at the two level. When he does that, Penenlope will know not to stop bidding below game and they can describe their hands further with their next bids in order to reach the best game contract.

Walter has 14 points, so a game forcing hand, but he doesn't have fit with Penelope's spades. Responding 2D or 2H would show a five card suit. But because sometimes, like here, you need to be able to say 'I have a game forcing hand' but you don't have fit or a biddable suit of your own, we use 2C in a more general way to show a game forcing hand that mey or may not have clubs. It's rather like the 1C opening in that way. Notice that to your partner, your bid where you have a real club suit (question 7) and this one look the same at the point where you respond 2C. You will clarify things with your next bid.