In Mandarin the pitch shape of a syllable is part of the word, not expression. The syllable ma is four different words depending on how the pitch moves — and a fifth, toneless, when it's light and unstressed. Tap each to hear it. 在普通话里，音节的音高走向是词的一部分，而非语气。同一个 ma 因调不同而成四个不同的字——再加一个不带调的轻声，共五个。点击即可听。
The pitch scale runs 1 (low) to 5 (high). Tone 1 holds high; tone 2 rises; tone 3 dips low then lifts; tone 4 drops sharply. The neutral tone is short and light, its pitch borrowed from the syllable before it. 音高从 1（低）到 5（高）。一声保持高平，二声上扬，三声先降后升，四声急降。轻声短而轻，音高取决于前一个音节。
Tones can shift in connected speech (tone sandhi): two 3rd tones in a row make the first rise (nǐ hǎo → ní hǎo), and 不 / 一 change tone before certain syllables. These are effects above the single syllable — the bank teaches each syllable in isolation; sequences come later. 在连读中声调会变（变调）：两个三声相连，前一个变二声（nǐ hǎo → ní hǎo）；不、一在某些音节前也变调。这些是音节之上的现象——音节库先教单音，连读留待后续。