Chinese Phoneme Control

Control Chinese pronunciation with tone-number pinyin

Overview

Chinese phoneme control uses pinyin with tone numbers, also known as tone3 pinyin. Wrap one syllable in each <|phoneme_start|> and <|phoneme_end|> tag.

我是一个<|phoneme_start|>gong1<|phoneme_end|><|phoneme_start|>cheng2<|phoneme_end|><|phoneme_start|>shi1<|phoneme_end|>。

This format is especially useful for polyphonic characters, names, and domain-specific terms where the default reading may be ambiguous.

Tone Numbers

Put the tone number at the end of each pinyin syllable:

Tone	Example	Description
1	ma1	High level
2	ma2	Rising
3	ma3	Dipping
4	ma4	Falling
5	ma5	Neutral

Use lowercase pinyin and keep punctuation outside the phoneme tag.

Multi-character Words

For a multi-character word, place adjacent phoneme tags in the same order as the original characters:

Standard: 我是一个工程师。
With phoneme control: 我是一个<|phoneme_start|>gong1<|phoneme_end|><|phoneme_start|>cheng2<|phoneme_end|><|phoneme_start|>shi1<|phoneme_end|>。

You can also tag only the ambiguous character and leave the rest of the sentence unchanged:

请把这个字读作<|phoneme_start|>hang2<|phoneme_end|>。

Polyphonic Characters

For polyphonic characters, choose the pinyin that matches the phrase meaning:

重庆: <|phoneme_start|>chong2<|phoneme_end|><|phoneme_start|>qing4<|phoneme_end|>
重要: <|phoneme_start|>zhong4<|phoneme_end|><|phoneme_start|>yao4<|phoneme_end|>

银行: <|phoneme_start|>yin2<|phoneme_end|><|phoneme_start|>hang2<|phoneme_end|>
行走: <|phoneme_start|>xing2<|phoneme_end|><|phoneme_start|>zou3<|phoneme_end|>

音乐: <|phoneme_start|>yin1<|phoneme_end|><|phoneme_start|>yue4<|phoneme_end|>
快乐: <|phoneme_start|>kuai4<|phoneme_end|><|phoneme_start|>le4<|phoneme_end|>

Generate Pinyin

The training pipeline uses the pypinyin dictionary and converts entries to tone3 pinyin. The helper below mirrors that behavior for single characters:

pip install pypinyin

from pypinyin.contrib.tone_convert import to_tone3
from pypinyin.pinyin_dict import pinyin_dict


def chinese_char_to_pinyin(char: str) -> str | None:
    pinyin = pinyin_dict.get(ord(char))
    if pinyin is None:
        return None
    if "," in pinyin:
        raise ValueError(f"{char} has multiple readings; choose one manually")
    return to_tone3(pinyin)


print(chinese_char_to_pinyin("工"))
# gong1

Phrase-level words can require a phrase dictionary or manual selection. For example, 重 should be chong2 in 重庆 but zhong4 in 重要.

Practical Tips

• Use one phoneme tag per Chinese character or syllable.
• Keep Chinese punctuation, brackets, and spaces outside the tag.
• Choose readings manually for names and polyphonic characters.
• Use ma5-style tone 5 when you need to mark a neutral tone explicitly.