Бридж ойынындағы Акол жүйесі

Bridge card game bidding system used in Britain and elsewhere

Acol is the bridge bidding system that, according to The Official Encyclopedia of Bridge, is "standard in British tournament play and widely used in other parts of the world". It is a natural system using four card majors and, most commonly, a weak no trump.

Acol is named after the Acol Bridge Club in London NW6, where it originated in the early 1930s. The club was founded on Acol Road, According to Terence Reese, the system's main devisers were Maurice Harrison Gray, Jack Marx and S. J. "Skid" Simon. Marx wrote in the Contract Bridge Journal of December 1952, that " the Acol system was pieced together by Skid Simon and myself the best part of 20 years ago." In another account, Marx and Simon
text=progressively, infected and re infected each other with the virus of the game. In interminable slow walks they would wander round and round the quiet streets, endlessly discussing the refinements of the enthralling game. Out of these conversations—surely a strange gestation—was born Acol as we know it and play it to day.|sign=Guy Ramsay|source=Aces All (1955), Museum Press Limited, London, p. 170. The first book on the system was written by Ben Cohen and Terence Reese. Skid Simon explained the principles that lay behind the system, and the system was further popularised in Britain by Iain Macleod. The Acol system is continually evolving but the underlying principle is to keep the bidding as natural as possible. It is common in the British Commonwealth but rarely played in North America. Ely Culbertson and his partner Teddy Lightner had visited the Acol Bridge Club in 1934, after which members S. J. Simon and Jack Marx became interested in bridge bidding theory. Simon and Marx soon afterwards began a discussion that eventually led to the first version of the Acol system.

Acol is an unregulated system. There is no Acol governing body and no single publication containing the "official" Acol (unlike, for example, Standard American Yellow Card). It can be compared to a living language since it is liable to change at the whim of users. The main versions of Acol in use today are:
Acol: unregulated Acol, from the simple to the complex, remains in common use throughout the UK. At any one time the version in most common use will be known as "Standard Acol" although this term will mean different things to different players and is sometimes confused with Standard English Acol. Standard English Acol (originally called simply "Standard English") or Bridge for All (BfA) Acol. Developed by the English Bridge Union in 1996, and designed to facilitate the learning of bridge and to provide standardised guidance to novices, intermediate players and their teachers. This variant uses the weak 1NT opening (12–14 points) and strong two opening bids. Simple conventions such as Stayman, Blackwood and Transfers are included at various stages in the learning process. It has been widely promulgated by the EBU and by EBUTA in particular, but the exact form is used mainly by those who have learned their bridge recently and those who taught them. Modern Acol: a broad term for modern systems based on standard Acol but adding some additional conventions, particularly transfers and alternative ways of playing opening two bids, as described below. Varies between partnerships, but typically includes two suited overcalls, cue bids, checkback Stayman, Jacoby 2NT and Roman Key Card Blackwood. Benjaminised (Benji) Acol: recognising that strong two opening bids occur rarely, the 2 and 2 openings are used as weak two bids to show weak hands containing long suits (under 10 HCP and a 6 card suit). Very strong hands (8 or more playing tricks, equivalent to an Acol Strong Two) are shown by an opening bid of 2 which forces a 2 response allowing suits to be shown. The strongest hands (e. g., 23 or more points or a game force hand, equivalent to the Acol 2 opening) are shown by an opening bid of 2. Reverse Benji: identical to Benji except that the 2 and 2 bids are switched in meaning. A 2 opening bid is now the strongest bid, as in basic Acol. Modern Acol with Three Weak Twos: uses the Standard American pattern where 2 is the only strong bid and 2, as well as 2 and 2, is a weak two bid. Proponents consider that a Benji 2 bid on 23+ or a game forcing hand is too infrequent (about 0.2% of hands) to use up a whole opening bid. A weak two in diamonds is much more common (1.2%). However, some definition is lost on strong hands aiming for slam. Acol with Multi 2: this variant of Acol makes use of the Multi 2 diamonds convention, where 2 shows a variety of hands including weak two bids in hearts and spades. The 2 bid is used as in standard Acol (23+ points). Various uses are made of the 2 and 2 bids, with traditional strong twos or Lucas twos being some popular methods.

The following is a brief summary of the Standard Acol as from 2000 to 2005. Standard Acol has not changed significantly since that time.

The responses below assume a weak (12–14) NT opening: players should adjust the point ranges for responses if playing a different opening range. 2 — Stayman. Opener responds 2 with no four card major, 2 with a four card heart suit and 2 with four spades (denies four hearts). Forcing for one round. 2 of any other suit — weak takeout, opener must pass. Some players make use of transfers. 3 of a suit — shows a strong hand with a five card suit, forcing to game. 2NT — 11–12 HCP. invites game if opener is maximum (i. e., for a weak opening NT, if opener has 14 or a good 13 HCP). 3NT — to play. 4 — asks for aces. (Gerber)
4, 4 — to play. 4NT — slam invitation, opener bids 6NT with a maximum. 5NT — slam invitation, opener bids 6NT unless a minimum. Note: some play as invitation to 7NT; opener bids 6NT if minimum, 7NT with a maximum.

3 — Baron. Opener bids his lowest four card suit. Forcing. (Stayman may also be used as in responses to 1NT; i. e., 3 shows no 4 card major). 3 of other suit shows a five card suit, forcing to game. Some players use transfers. Other responses as over 1NT.

2 — negative. Responder lacks the strength for a positive response. Unless opener rebids 2NT (balanced, 23–24 HCP, which may be passed), the sequence is forcing to game. 2NT — fairly balanced, 8 or more HCP. Some players take this as showing a minor. Forcing to game. 2 of a suit — at least five in the suit, the equivalent of an ace and a king in high cards. Forcing to game. 3 of a suit — Solid suit of at least six cards. Forcing to game.

2NT — negative. Responder lacks the strength for a positive response. Simple bid of a new suit — 8 or more HCP (or an Ace and a King), at least five in the suit. Forcing to game. 3 of opener's suit — 5–8 HCP, at least 3 card support. Forcing to game. 3NT — flat hand, 8–11 HCP. Not forcing.

Bid of new suit at lower level than first suit — minimum hand, 12–15 HCP, first suit has at least as many cards as second suit, non forcing. Bid of new suit at higher level than two of the first suit, but without jumping (a Reverse bid) — strong hand, 16–19 HCP, first suit has more cards (at least five) than second suit, forcing for one round. Jump in new suit — strong hand, about 19+ HCP over 1 level response or 16+ over 2 level response, first suit has at least as many cards as second suit, forcing to game.

The following bids assume a weak (12–14) NT opening.

By the time responder has to rebid, it is often clear what the best final contract should be, especially if either player has made a limit bid. If opener has bid two suits, responder can show preference between them. With a strong hand but uncertain whether a game contract is on or which game it should be, he can use fourth suit forcing to obtain further information.

A bid of the fourth suit at the 2 level by responder is a one round force, usually asking opener to bid no trumps with a stopper in the fourth suit. A fourth suit bid at the 3 level is similar, but forcing to game.

In common usage, the term Acol is understood to refer to a four card majors system. For hybrid systems using the weak NT opening with one or both five card majors, a different terminology is preferable. Five card spades or 5 4 4 3 system; the 1 opening shows at least 5 spades, and a hand with 4 spades and 4 3 3 3 shape is opened 1. A 1 opening may be on only 3 cards. This can also be played so that the 1 opening either guarantees 5 hearts or 4 cards in both majors. In this case a 3 4 3 3 shape would also be opened 1. Five card majors with a weak NT; both 1 and 1 openings guarantee 5 cards. Sometimes known as the "Third Way" system; the first system of this type was the Kaplan–Sheinwold system. To handle 4 4 3 2 hands with both 4 card majors, this needs either a "short club" (1 can be as few as 2 cards) or both a prepared 1 and 1 which could be just 3 card suits. Five card majors are more commonly used with a strong no trump, as in Standard American.