The Water Radical — Writing 清, 深, 波 and 流 with San-zui

The Third Stroke Points the Way

The water radical, san-zui (氵), is three strokes. As a standalone character, the left-side strokes of 水 run vertically. As a radical they change: the first two strokes angle downward-right, and the third turns horizontal — a brief horizontal arrest that points toward the right component.

When I write the third stroke as vertical rather than horizontal, the left side of the character becomes heavy and closed. When I turn it horizontal, something settles: the right component now has a shelf to stand on. I noticed this clearly during October practice, working on 清 on half-size paper. On the days I let the third stroke drift vertical, the right side 青 compressed inward. On the days I held it horizontal, 青 extended rightward and the character opened. Whether that opening is right depends on the character — but for 清 (clear, pure), the horizontal version suits what the word means.

清 and 深 — Holding a Vertical Structure

The right side of 清 is 青, which stacks a horizontal bar above a 月-derived lower section — a vertical structure. The radical's horizontal third stroke gives that vertical structure a foundation.

When I practice writing autumn kanji, I often pair 清 and 澄 (serene), because both carry the water radical alongside a tall right component. Both ask the same question: does the radical's third stroke turn horizontal enough? When it does, the right side gains height. For 清 in particular, that height produces the quality the character needs — upright and clear.

深 (deep) has eleven strokes, more than most characters with the water radical. The right side carries a 宀-like form above and a 木-derived form below — coverage and extension in a single right component. For this character I write the third stroke of the radical slightly shorter and narrower than I would for 清, aligning its end with the left edge of the 宀 above. If the radical's third stroke extends too far right, the roof of 宀 appears to sit on top of the dots, and the character closes in. This fine adjustment — changing how the same radical reads depending on the character — is the principle that applies across all radical-based characters: the radical sets the anchor, and the right component reads from there.

波 and 流 — Guiding the Horizontal Sweep

The right side of 波 (wave) ends in a long rightward sweep, the final stroke of 皮. The radical's condition determines how far that sweep should travel.

Early in my practice of 波, I instinctively extended the sweep of 皮 as far as the white space allowed. Space pulls the brush. What corrected this was paying attention to the entry into that final stroke — not its length, but the sharp upward angle at the start. Speed and line quality are bound together in that stroke: entering quickly and at a steep angle produces a tip that stands, which is what 波 needs. The radical has to be compact to create the conditions for that entry to be decisive.

流 (flow) is the most kinetic of the four. The right side descends in an S-shaped arc from a flag-like top — one continuous movement held inside the character. The water radical functions as the starting signal. When the three dots are held tight and the hand carries the direction of the third stroke directly into the first stroke of the right side, the whole character moves. The moment between the final dot and the first right-side stroke is where the flow begins or does not.

I do not pause between the radical and the right side of 流. The direction is already in the hand when the last dot lands — and if the hand waits, the direction leaks away.