Bidding after opening 1♣/1♦ takes place according to Rubensohl scheme if the first opponent bid 2♣/2♦/2♥/2♠.

Answers as far as possible:

• • double - negative double;

  • 2♦/2♥/2♠ - any remaining available 2 level bids are natural and to play;

• 3 bellow the opponent suit - 14+ HCP, forcing;

  • • if the opponent suit is major - the other major four;

    • else - at least one major,

• • 3 bellow the partner suit if it is 3+ - support, 10+ HCP;

  • 2NT/3♣/3♦/3♥ - respectively 5+♣/5+♦/5+♥/5+♠:

    • • 8+ HCP if the suit is 6+;

      • 14+ HCP in other cases,

  • 3♠ - no majors, no stopper, 14+ HCP.