Openings · A10–A39

English Opening

A flank pawn first: fight for d5 from the side, and keep the centre pawns for later.

1.c4played as White

The idea

1.c4 stakes a claim on d5 without putting a pawn where it can be attacked. Very often it becomes a Sicilian with colours reversed — 1…e5 is Black's Sicilian structure a tempo down — and White's extra move is worth exactly as much as knowing what to do with it.

The opening's real advantage is transpositional. It can become a Queen's Gambit, a Catalan, a King's Indian Attack, or stay a pure English with a fianchetto and a slow queenside squeeze, and the choice is made after seeing what Black commits to.

Practise the line

You play White; the other side answers on its own. Nothing here is saved or graded.

Your move 1 of 10/1

1.c4

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Common mistakes

Three that come up again and again below master level. Each is ordinary opening theory — a named trap, or the error every coach corrects — not a statistic, and not drawn from anybody's games.

Grabbing the centre too early

1.c4 e5 2.d4 exd4 3.Qxd4 Nc6

The mistake: Playing d4 at once, as though 1.c4 were a first move to be corrected.
Why it costs: 3…Nc6 hits the queen and Black develops with tempo. The flank move only pays for itself if the centre is opened when the pieces are ready — otherwise White has spent a move on c4 and then handed the initiative back.
Instead: 2.Nc3 or 2.g3 first. In the Reversed Sicilian the break is d4 later or f4 sooner, and both need pieces out before pawns move.

The Symmetrical, opened by hand

1.c4 c5 2.Nf3 Nf6 3.d4 cxd4 4.Nxd4 e5

The mistake: Trading on d4 in the Symmetrical and leaving the knight where it can be hit.
Why it costs: 4…e5 kicks the knight immediately and 5.Nb5 d5 frees Black's game entirely. What was meant to be a space advantage turns into a knight on the rim and a black pawn centre.
Instead: 3.Nc3 and 4.g3, keeping the symmetry until the fianchetto is in place. The break comes later, when …e5 can be met by a piece.

Fianchettoing into ...e4

1.c4 e5 2.g3 Nf6 3.Bg2 c6 4.Nf3 e4

The mistake: Developing the knight to f3 after Black has prepared …e4 with …c6.
Why it costs: 4…e4 gains space with tempo, drives the knight to a worse square and takes the long diagonal away from the bishop you have just fianchettoed. The move …c6 was the warning, and it is easy to read as a quiet move.
Instead: 4.d3 first, or 4.Nc3, so that …e4 can be answered by taking or undermining. Against the …c6 and …d5 set-up, White's play is against the d5 pawn.

Try it on one of your own

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