PLAYING 2/1 AFTER AN OPEN IN A MAJOR AND RESPONSE 1NT HOW TO DESCRIVE A GAME FORCE (GF) HAND WITH 18-20 points?    

THESE RULES APPLY ALSO FOR (RESPONDER) PASSED HANDS

RULE#1: points for an open hand are the addition of hcp (high card points) more suit length after 4 cards, so a hand with 5 cards length have +1 point, a hand with two suits 5-5 have +2 points, a hand with 6 cards have +2 points, a hand with 7 cards have +3 points and so on.
This exclude distributional points for shortness (dubleton=1 / singleton=2 / void=3) in the open hand but for a Responder avaliation with 4 cards support in Opener's suit this upgrade the value of Responder's hand.

RULE#2: Opener's second bid jumping to another suit, after response in level 1, means 5-5 or 6-5 distribution and shows 18-20 points (not hcp).

RULE#3: When Opener has 18-20 points (not hcp), after response in level 1, if he has distribution 54xx or 6xxx or 7xxx (not 55xx or 65xx) he jumps to 2nt showing a GF hand. 

1) AFTER 1 OPEN
a) when there are 2 suits 5-5 or 6-5
Opener Responder
  1         1nt
   ?
  3  <= 55 GF 18-20 points
............. AK732 AQJ102 Q2 2    AKJ342 AQJ42 Q4
  3  <= 55 GF 18-20 points
............. AK732 Kx AQJ102 2    KQJ932 3 AKQJ4 6
  3  <= 55 GF 18-20 points
............ AQ10732 - 2 AKJ102    KQJ93 A4 2 AKJ102

b) when there are 2 suits 5-4 or 6xxx or 7xxx
Opener Responder
  1         1nt
  2nt  <= GF unless misfit is found
..............  ?
.............. 4 <= 3 cards support 5-7 hcp (probable 4333)
.............. 3 <= 3 cards support 10-11 hcp
.............. 3 <= sign-off 6+ cards
.............. 3 <= sign-off 6+ cards
.............. 3 <= artificial bid - asking for hand explanation
   ?
  3  <= 54xx   GF 18-20 points
  3  <= 54xx   GF 18-20 points
  3  <= 6xxx     GF 18-20 points
 3nt  <= 54xx   GF 18-20 points
              now Responder decide and bidding 4 is sign-off
  4  <= 7+ cards like  AKJ10874 4 AK9 Q2 or AQ98743 42 AKQ 2
              so Responder pass or having 10-11 hcp
              with 2 cards support and 1 ace (fundamental) can try Slam.

RULE#4: When Opener has strong 6-4 solid hand like AK108xx AKQx or 7-4 distribution like AKxxxxx AKJ10 after second bid 2nt GF and 3 the bid in 4 or 4 shows this rare type of hand.
Opener Responder
  1        1nt
  2nt       3 <= asking explanation
4/4    64m and maximum 4 losers hand

2) AFTER 1 OPEN we must consider partnership that play response 1 as natural 4+ cards and partnership that play inverted nt where response of 1nt shows 5+ cards and response 1 shows up to 4 cards spades that means a response of 5-11 hcp and 4 or 3 or 2 or 1 or 0.
2;1 - response 1nt deny 4 cards:
a) when there are 2 suits 5-5 or 6-5
Opener Responder
  1         1nt
   ?
  3  <= 55 GF 18-20 points
............. K3 AK732 AQJ102 2 / 2 AKQJ6 AQ1092 Q2
  3  <= 55 GF 18-20 points
............ 5 AQ10732 2 AKJ102 / A5 KQJ93 2 KQJ106
              ?
             pass <= misfit hand
             3 <= 3 cards and 10-11 hcp
             3nt <= to play
             4 <= 5-7 hcp with 3 support minimum hand
             4m <= 4+ cards support and Slam interesting
             5m <= 4+ cards support and minimum hand         
        
b) when there are 2 suits 5-4 or 6xxx or 7xxx
Opener Responder
  1         1nt
  2nt <= GF unless misfit is found
..............  ?
.............. 4 <= 3 cards support 5-7 hcp (probable 4333)
.............. 3 <= 3 cards support 10-11
.............. 6 cards sign-off unless Opener second suit is Diamonds
.............. 3 <= artificial bid - asking for hand explanation
   ?
  3  <= 54   GF 18-20 points
  3  <= 6xxx GF 18-20 points
  3  <= 54  GF  18-20 points
 3nt  <= 54  GF 18-20 points
              now Responder decide and bidding 4 is sign-off
  4  <= 7+ cards like 4 AKJ10874 AK9 Q2 or 4 AK987432 AKQ 2
       so Responder pass or having 10-11 hcp with 2 cards support and 2 aces
      (fundamental) can try Slam.

2.2 - response 1nt shows 5+ cards - inverted nt:
a) when there are 2 suits 5-5 or 6-5
Opener Responder
  1         1nt  <= 5+ cards
  4       <= 3 cards support 18-20 points
  3       <= 4 cards - slam interesting GF 18-20 points
  2       <= not forcing - 3 or 4 support 12-14 hcp
  3  <= 55 GF 18-20 points
............. K3 AK732 AQJ102 2 / 2 AKQJ6 AQ1092 Q2
  3  <= 55 GF 18-20 points
............ 5 AQ10732 2 AKJ102 / A5 KQJ93 2 KQJ106
              ?
           pass <= misfit hand (possible void in )
             3  <= 6 misfit hand - sign-off
            3nt <= to play
             4m <= support 4+ cards in m and slam interesting
             5m <= support 4+ cards in m and minimum hand
 
b) when there are 2 suits 5-4 or 6xxx or 7xxx
Opener Responder
  1         1nt <= 5+ cards
  2nt <= GF unless misfit is found
..............  ?
.............. 3 <= 6 cards - possible misfit - sign-off
.............. 4 <= 3 cards support 5-7 hcp (probable 4333)
.............. 3 <= 3 cards support 10-11
.............. 3 <= sign-off 6+ cards
.............. 3 <= artificial bid - asking for hand explanation
   ?
  3  <= 54  4 cards support and 18-20 hcp
  3  <= 54   GF 18-20 points
  3  <= 6xxx GF 18-20 points
 3nt  <= 54  GF 18-20 points
              now Responder decide and bidding 4 is sign-off
  4  <= 7+ cards like 4 AKJ10874 AK9 Q2 or 4 AK987432 AKQ 2
       so Responder pass or having 10-11 hcp with 2 cards support and 2 aces
      (fundamental) can try Slam.
  4  <= to play 3 support and 18-20 hcp

RULE#5: When Opener have 18-19 hcp in 5332 hand after response 1nt Opener bids 3nt
Opener  Responder
1major     1nt
 3nt  <= 18-19 and 5332

RULE#6: When Opener have 16-17 points after response 1nt he bids like having 12-15 points, but if Responder bids again then he bids 2nt or support Responder`s suit showing 16-17 points.
Opener Responder
  1         1nt
  2         2
 2nt  <= 16-17 points invitation to 3nt

Opener  Responder
  1         1nt
  2         2 <= sign-off
  3  <= 16-17 points invitation to 4

RULE#7: After 1 major open and a response in 1nt Opener's second bid rebidding his suit in jump to level 3 means 6 cards with 16-17 points asking for 2 cards support and 8-9 points in Responder's hand.
Opener  Responder
  1         1nt <= deny 4
  3          ?
............. with  J104 6 AQ1092 K632 <= pass
............. with  2 96 AQ1092 K8762  <=  4
............. with  J10x K6 J1092 Q876 <= pass

RULE#8: After 1 major open and a response in 1nt Opener's second bid rebidding his suit at level 4 promise 8/9 tricks with assurance of solid suit in 6 cards with AKQJxx or in 7+ cards with AKQxxxx.
Opener Responder
  1         1nt
  4 <=  AKQ10874 4 AK9 Q2  or   AKQJ74 4 AK9 Q102
Opener Responder
  1         1nt <= deny 4 cards
  4 <=  3 AKQ108742 AQ10 J  or  Q96 AKQJ74 AK9 2


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