In its simplest terms, the "system" described as 2-over-1 game-forcing refers to the following 6 bids :

1 Diamond - 2 Clubs
1 Heart - 2Clubs
1 Heart - 2 Diamonds

1 Spade - 2 Clubs
1 Spade - 2 Diamonds
1 Spade - 2 Hearts

When responder uses a game-forcing "2-over-1" bid he is informing opener that he, too, holds at least opening-bid values. Accordingly, the partnership may leisurely proceed to the optimum contract without fear of being dropped below game. Opener then should show his "shape," without implying # of HCP.

As opener, what do you rebid?

You	Opponent	Partner	Opponent
1	Pass	2	Pass
??

(All answers/reasons given at end of lesson)

A)	B)	C)	D)	E)	F)
5 4 K Q 10 8 7 4 A J 3 K 4	3 2 Q J 10 8 7 A 4 A Q 5 4	A K J 2 A Q 8 7 6 A 5 4 2	A Q 3 K J 8 7 6 5 K Q 10 2	Q J 2 Q 9 7 6 4 Q 9 2 A Q	A 2 A K Q J 9 8 K 7 6 5 2

As responder, what do you bid?

You	Opponent	Partner	Opponent
1	Pass	2	Pass
2NT	Pass	??

G)	H)	I)	J)	K)
K J 3 A 2 K Q 10 8 7 4 3 2	4 2 A Q J A Q 8 7 6 5 A 7	4 A 5 A K Q 10 8 7 2 Q 3 2	4 3 A Q 2 K Q J 10 8 2 5 2	K Q J 10 3 A Q 10 8 4 A Q 5

Two-Over-One Abbreviation for Game Forcing GF (and "forcing" 1NT) –(continued)

An important Conventional 2NT response to a weak two-bid that asks opener to show a high card in a side suit if he is not with a minimum preempt feature of the 2/1 Abbreviation for Game Forcing GF system is to employ a 1NT bid (by an unpassed hand) in response to a major-suit opening bid as forcing (or semi-forcing) for one round. Unlike Standard American, this bid is not limited to 6 to 9 HCP. Normally, it shows 6 to 12 HCP.

If 1NT is totally forcing, opener CANNOT pass! If he has nothing special to say, he must invent a bid, typically in a 3-card minor.

For example, after 1 ? 1NT, if opener holds the following hand:

A J 10 8 2
9 7 3
A 2
K J 2
, the appropriate rebid is 2. Opener cannot rebid his major since this would show a 6 card suit. He cannot make a 2 call because a rebid of the other major shows at least a 4-card suit. Lastly, he can't pass if 1NT is forcing, and he cannot bid 2, a 2-card suit. (Personally, I prefer to use 1NT as "semi-forcing"—so that opener can pass with a hand like the one above.)

Openers's Rebids after 1NT forcing:

2 minor – at least a 3-card suit (note: 2 can be exactly 4=5=2=2 if not strong enough to reverse)
2 new major – at least a 4-card suit (if reverse, shows extras)
2 same major – at least a 6-card suit, NF
2NT – more than a strong notrump, balanced
3-level – same as over a normal 1NT response

Examples for opener after 1-1NT:

L)	M)	N)	O)	P)
A Q 9 8 2 A 5 2 Q J 2 7 3	Q J 10 6 5 2 A 5 2 Q J 2 A	A K Q 5 2 A K Q 10 2 10 5 2 --	A J 5 4 2 A K 2 K 2 K 8 3	A Q J 10 5 4 2 A J 2 K 2 3

Responders's actions after 1NT forcing:

New suit on 2-level : Non-forcing
Preference to opener's Major : Typically weak, usually 2-card support
Raise of opener's second suit: Invitational, natural
2NT : Invitational, Natural
Jump Raise of opener's major: 3-card limit raise

Examples for responder after 1-1NT-2:

Q)	R)	S)	T)	U)
6 10 3 2 Q 5 4 2 A K J 6 4	A 5 2 Q J 9 8 2 K 10 2 10 9	Q 7 A Q 6 2 9 8 7 6 5 4 2	10 Q 10 9 8 K Q 10 8 7 A 8 2	4 K Q 10 8 7 6 Q 4 3 2 J 2

General notes:

2-over-1 is game-forcing as long as responder is not a passed hand and there is no interference bidding (so, in competition, 2/1 is NOT game forcing). Some partnerships may choose to play that if responder rebids his original suit, the game-forcing Conventional 2NT response to a weak two-bid that asks opener to show a high card in a side suit if he is not with a minimum preempt feature is off.

The 2/1 Game Forcing system is really an outgrowth of Standard American and 5-card Majors and many of the methods and conventions employed are alike. There are many more details—this mini-lesson is intended only as a brief overview of the principles.

Larry's audio presentation to the ABTA on 2/1 Abbreviation for Game Forcing GF in New Orleans, 2010

Larry's 64-page 2/1 Abbreviation for Game Forcing GF workbook

Webinars on 2/1

ANSWERS (with further clarification)

A) 2 (Repeat the 6-card suit)
B) 3 (Forcing, of course—until at least game is reached)
C) 2 (Natural again – and just coincidental that you have extras)
D) 3 (Splinter bid—no need to ever jumpshift naturally into a new suit)
E) 2NT (Natural—also, not promising extras)
F) 3 (An unnecessary jump should show a solid suit)

G) 3NT
H) 3 (Forcing, of course)
I) 3 (No need to rush into Blackwood)
J) 4 (Most players use this jump to show a minimum with all the pictures in the suits bid)
K) 4NT (Quantitative)

L) 2 (But pass if playing 1NT as semi-forcing)
M) 2
N) 3
O) 2NT
P) 4

Q) 3 (Invitational)
R) 3 (This sequence is used to show a 3-card limit raise)
S) 2 (This could be a very bad 3-card raise, but is usually a hand like this—a "false-preference")
T) 2NT
U) 2 (Natural, nonforcing)

A 2-over 1 game force is not alertable.

The 1NT response is announced (by the opener) as "Forcing" or "Semi-forcing" -- whatever the partnership has agreed.