Thankfully, we rarely open 2N — also known as slam-killer —, and so our responses to 2N, 1-1-2N and 1-1-2-2-2N are very simple:

• 3 - Stayman
• 3, 3 - Transfers
• 3, Minor suit Stayman
• 3N - to play
• 4 - Gerber
• 4, 4 - Transfers

To show a minor one-suiter, start 3 and bid the minor at the 4-level (This does not promise a major with a longer minor)

An alternative approach is:

• 3 - Stayman
  • After opener shows his major or lack of a major, responder can bid a minor at the 4 level, promising that suit and a major not bid by opener
• 3, 3 - Transfers
• 3, forces 3N
  • Responder then either passes or bids 4, a transfer to
• 3N - Transfer to 4
• 4 - Gerber
• 4, 4 - Transfers