Lesson 5 · Foundational Components

Counting to Ten (Almost): 一 / 二 / 三 / 十

Numbers are some of the highest-frequency characters in the language, and three of today's four are about as simple as Chinese gets: 一, 二, and 三 are literally tally marks — one, two, and three stacked horizontal strokes. The fourth, 十 ("ten"), is the more valuable one: once you have it, you can read and form every number from 10 to 99 by combining digits you already know, without learning a single new character for any of them.

Your four new components

一
 
yī
one
1 stroke
二
 
èr
two
2 strokes
三
 
sān
three
3 strokes
十
 
shí
ten
2 strokes

Quick recall — click each card to flip it:

一
yī — one
二
èr — two
三
sān — three
十
shí — ten
The tally pattern stops at three — don't extend it. 一/二/三 are stacked horizontal strokes, so it's tempting to guess "four" is four stacked strokes. It isn't: 四 (sì) is a completely different, enclosed shape, arriving next lesson. This is worth flagging now, before you guess wrong, rather than after — the same principle Lesson 4 applied to 出 and 山: a pattern that looks like it should continue doesn't always.

Where 十 really comes from

Wiktionary records two competing theories for 十's origin, and you don't need to pick one to use the character: it may originally have depicted a needle (针, later borrowed purely for its sound to mean "ten"), or a knotted cord used for counting or tallying. What's clearer is the shape's evolution: oracle-bone forms of 十 are mostly a single vertical stroke — sometimes with a small dot partway down — and only later did a horizontal stroke get added, producing the cross shape you write today. (Wiktionary: 十)

Stroke order

一, 二, and 三 have nothing to teach beyond "top to bottom" — each is just that many horizontal strokes, stacked. 十 follows the same horizontal-before-vertical rule you already know from 木 in Lesson 1:

  1. 一horizontal, left to right
  2. 丨vertical, top to bottom, crossing the horizontal

Where the payoff shows up: a third combining pattern

You've now seen components fuse into a new character (好 = 女+子), characters sit side by side as a word (出口 = 出+口), and now a third pattern: characters combining by arithmetic. The position relative to 十 changes the operation:

十 + 一 → 十一 shí yī — 11 (ten, plus one — digit after 十 adds)

二 + 十 → 二十 èr shí — 20 (two, times ten — digit before 十 multiplies)

二十 + 三 → 二十三 èr shí sān — 23

That last one combines both rules at once: 二十三 is literally "two-ten-three," i.e. (2×10)+3. Once a future lesson fills in 四 through 九, this same logic reads any number up to 99 — nothing new to memorize, just 十 plus arithmetic you already do.

Check your recall

Which character means "ten"?

How many strokes is 三?

二十三 (二 + 十 + 三) represents the number:

In 二十 (two-ten), the digit before 十 acts to:

Go further

For the full etymology of any character above, see the Wiktionary entry linked, or the Outlier Dictionary of Chinese Characters for the rigorous version.

Out in the world: 十 and combinations like 二十/三十 turn up on price tags, receipts, dates, and platform/gate numbers anywhere characters are used instead of Arabic numerals — and you can already read prices like 十三 (13) or 二十一 (21) cold.

Something unclear, or want to go deeper on any of this? Ask your teacher — that's what these sessions are for.