Tone Sandhi

01

The Rule

Only the LAST syllable of a phrase is said the way it is written. Every syllable before it moves to a different pitch. Where a syllable stands is the only thing that decides this — never what it means.

That is what you just heard: khuànn was not last, so it moved; tsheh was last, so it did not.

老師 (lāu-sulāu-sulau7-su1) teacher does the same in the other direction. lāu is written flat, in the middle of your range, and comes out low instead. su is last, and is exactly as written.

02

A Phrase, Not A Word

The shift does not stop at the edge of a word. A whole phrase has one final syllable, and everything ahead of it moves.

• 伊是學生。

  i sī ha̍k-singi sī ha̍k-sengi1 si7 hak8-sing1

  She is a student.

Four syllables, and only the last is said as written:

• i is written high and flat — you hear it a step lower
• sī is written flat in the middle — you hear it low
• ha̍k is written high and clipped — you hear it clipped and low
• sing is last, so it stays high and flat

• 𪜶是朋友。

  in sī pîng-iúin sī pêng-iúin1 si7 ping5-iu2

  They are friends.

Same shape: three syllables move, and only iú is said as it is written.

03

Syllables That Stop Short

A syllable ending in p, t or k is cut off rather than held — that is the ha̍k above. These have only two pitches, high and low, and the shift simply swaps them: a high one is heard low, a low one is heard high. Syllables ending in h move by a rule of their own, which can wait.

04

The Whole Pattern In One Line

Once the tone numbers are familiar, everything above fits on a single line: 1 → 7 → 3 → 2 → 1, with 5 → 7 joining from the side, and 4 ↔ 8 for the clipped ones.

Read it to check what you just heard. Never to work out what to say next — nobody runs that loop while talking.

05

Why The Spelling Never Changes

The Tâi-lô here always writes the tone a word has ON ITS OWN, the way a dictionary lists it, and never the shifted one. That is standard, and it is what keeps a word looking the same everywhere you meet it — at the price that what you hear will often differ from what you read. Expected, not an error.

Tap any word to see all three side by side: the tone it is written with, the tone it has by itself, and the tone it takes when a phrase carries on past it.

06

How To Learn It

Learn each word as a single melody, the way you learned where the stress falls in an English word, and copy the audio whole. The rules above are for recognising what happened to a word you already know — not for arithmetic in the middle of a sentence.