围棋最基础的战术 — 威胁吃掉对方的棋子
叫吃（日语：アタリ，Atari）是围棋中最基本、最重要的战术概念之一。当一颗棋子或一组棋子只剩下最后一口气（自由点）时，对方下一手就可以将其吃掉，这种状态就叫做"叫吃"。发起叫吃的一方是在威胁对方：如果你不应对，我下一步就吃掉你的棋子。
理解叫吃是学习围棋的第一步。每个初学者都必须学会识别叫吃的形状，判断哪些棋子处于危险之中，以及如何正确地应对叫吃。叫吃不仅是防守技巧，更是进攻的利器——通过连续叫吃，你可以迫使对方按照你的节奏走棋，最终获得优势。
要理解叫吃，首先需要理解"气"的概念。每颗棋子放置在棋盘上后，与它直接相邻（上下左右）的空交叉点就是它的"气"。当一颗棋子的所有气都被对方堵住时，这颗棋子就被吃掉（从棋盘上移除）。
在棋盘的不同位置，棋子拥有的初始气数是不同的：
因此，角上的棋子最容易被叫吃，因为它只有2口气，对方只需要一步就能将它逼到叫吃的状态。而中央的棋子有4口气，相对更安全。
在边上，棋子只有3口气。当对方堵住其中2口气后，棋子就处于叫吃状态。边上的叫吃是最常见的形式之一，因为很多战斗都发生在棋盘的边缘地带。
边上的叫吃：白子只剩1口气（绿点），黑子正在叫吃
在这个图中，白棋位于边上，被两颗黑棋包围，只剩下一个绿色标记的自由点（气）。如果轮到黑棋下，黑棋可以在绿色位置落子，吃掉白棋。白棋必须立即应对——要么逃跑（向绿色位置延伸），要么在别处下出更有价值的棋。
角上的叫吃更加危险，因为角上的棋子本身只有2口气。只需对方一步棋就能形成叫吃，两步就能吃掉。所以角上的作战需要格外小心。
角上的叫吃：白子在角上只剩1口气
角上的白棋只有两个相邻点，黑棋占据了其中一个，白棋只剩下一口气。这是最简单的叫吃形式，也是初学者最先遇到的情况。
在棋盘中央，一颗棋子有4口气，要叫吃它需要堵住3口气。虽然中央叫吃出现的频率较低，但在中盘战斗中经常出现多子互相叫吃的复杂局面。
中央的叫吃：白子被三面包围，仅剩1口气
白棋在中央被三颗黑棋包围，只剩一口气。如果黑棋落在绿色标记处，白棋就被吃掉。白棋需要向下方逃跑或者做出其他应对。
当你的棋子被叫吃时，你有几种选择：
最直接的应对是向空位延伸，增加棋子的气数。但要注意，如果延伸后对方可以继续叫吃（形成"征子"），那么逃跑可能是无用的。
如果附近有己方的棋子，可以通过连接来增加整个棋块的气数。连接后的棋块更加安全，不容易被吃掉。
有时候，被叫吃的棋子价值不大，救它的代价太高。这时候可以放弃这颗棋子，转而在棋盘其他地方下出更有价值的棋。学会适时弃子是提高棋力的重要一步。
高级技巧——不去救被叫吃的棋子，而是去叫吃对方的棋子。如果你的反叫吃威胁更大，对方就不得不先应对你的威胁，你的棋子反而安全了。
叫吃不仅是防守概念，更是强大的进攻手段。通过巧妙的叫吃，你可以：
Atari is one of the most fundamental and important tactical concepts in Go (Weiqi/Baduk). When a stone or group of stones has only one liberty (freedom point) remaining, the opponent can capture it on the very next move. This state is called "atari." The player who places a stone in atari is essentially threatening: "If you don't respond, I will capture your stone on my next turn."
Understanding atari is the very first step in learning Go. Every beginner must learn to recognize atari shapes, identify which stones are in danger, and know how to respond correctly. Atari is not just a defensive concept — it is also a powerful offensive weapon. Through consecutive atari moves, you can force your opponent to play according to your tempo and ultimately gain an advantage.
To understand atari, you first need to understand the concept of "liberties." When a stone is placed on the board, the empty intersections directly adjacent to it (up, down, left, right — not diagonal) are its liberties. When all of a stone's liberties are occupied by opponent stones, that stone is captured and removed from the board.
The number of initial liberties depends on a stone's position on the board:
Therefore, stones in the corner are the most vulnerable to atari — they only have 2 liberties, so the opponent needs just one move to put them in atari and two moves to capture them. Stones in the center, with 4 liberties, are relatively safer.
On the edge of the board, stones have only 3 liberties. When the opponent blocks 2 of those liberties, the stone is in atari. Edge atari is one of the most common forms because many battles take place along the sides of the board.
Edge atari: White has only 1 liberty left (green dot), Black is threatening capture
In this diagram, a white stone sits on the edge, surrounded by two black stones, with only one liberty remaining (marked by the green dot). If it is Black's turn, Black can play on the green position to capture the white stone. White must respond immediately — either escape by extending toward the liberty, or play elsewhere if the stone is not worth saving.
Corner atari is even more dangerous because stones in the corner inherently have only 2 liberties. It takes just one move from the opponent to create an atari, and two moves to capture. Therefore, fighting in the corners requires extra caution.
Corner atari: White in the corner with only 1 liberty left
The white stone in the corner has only two adjacent points, and Black occupies one of them, leaving White with just one liberty. This is the simplest form of atari and the first situation beginners encounter.
In the center of the board, a single stone has 4 liberties, so putting it in atari requires blocking 3 of them. While center atari occurs less frequently with single stones, complex middle-game battles often produce situations where multiple groups are placing each other in atari simultaneously.
Center atari: White surrounded on three sides, only 1 liberty remaining
The white stone in the center is surrounded by three black stones with only one liberty left. If Black plays on the green-marked position, the white stone is captured. White needs to escape downward or find another response.
When your stone is in atari, you have several options:
The most direct response is to extend into an empty space, increasing the number of liberties. However, be careful — if the opponent can continue putting you in atari after you extend (forming a "ladder"), then running may be futile.
If you have friendly stones nearby, you can connect to them to increase the total liberties of the group. A connected group is much stronger and harder to capture.
Sometimes the stone in atari is not very valuable, and the cost of saving it is too high. In such cases, you can abandon the stone and play a more valuable move elsewhere on the board. Learning when to sacrifice is a crucial step in improving your Go skills.
An advanced technique — instead of saving your stone in atari, you put your opponent's stones in atari. If your counter-atari poses a greater threat, your opponent must respond to your threat first, and your original stone may end up safe after all.
Atari is not just a defensive concept — it is a powerful offensive tool. Through clever use of atari, you can: