3♣ | -3♦ | A forcing enquiry merely asking which Major is held. Opener bids their 4-card suit | ||
-3♥/♠ | show the 4-card Major. Now: | |||
-3NT | is 100% "to play" | |||
-4♣ | is invitational, but not forcing. | |||
-4♦ | is Beta, but since Responder will not know whether Responder is implicitly agreeing the Major or Clubs, no Epsilons are permitted and Responder must set the final contract over the Beta Response. | |||
-3♥ | is Eta in Hearts, but has the extra 1st step inserted to show no 4-card Heart suit. If Responder is 16+ with 4+-card support for both Majors, they should Ask in Spades first. | |||
-3♠ | shows 4-card Spades. Now: | |||
-3NT | is "to play" | |||
-4♣ | is Gamma in Clubs. Asking Bids now established. | |||
-4♦ | is Beta, but No Epsilons are permitted and Responder must set the final contract over the Beta response. | |||
-3NT | and upwards are Eta Responses for Hearts. Asking Bids now established. | |||
-3♠ | is Eta in Spades, but has the extra 1st step inserted to show no 4-card Spade suit. | |||
-3NT | shows 4-card Hearts. Now: | |||
-4♣ | is Gamma in Clubs. Asking Bids now established. | |||
-4♦ | is Beta, but No Epsilons are permitted and Responder must set the final contract over the Beta response. | |||
-4♥ | is Eta in Hearts. Asking Bids now established. | |||
-4♣ | and upwards are Eta responses for Spades. Asking Bids now established. | |||
-3NT | Natural and "to play" | |||
-4♣ | is Gamma in Clubs unless Responder is a passed hand, in which case it is an unbalanced invitation with 4+ Clubs. |