Tones 调号

Mandarin, like all Chinese dialects, is a tonal language. This means that tones, just like consonants and vowels, are used to distinguish words from each other. Many foreigners have difficulties mastering the tones of each character, but correct tonal pronunciation is essential for intelligibility because of the vast number of words in the language that only differ by tone (i.e. are minimal pairs with respect to tone).
The following are the 4 tones of Standard Mandarin:
1. First tone, or high-level tone (阴平 yīnpíng, literal meaning: yin-level): a steady high sound,
as if it were being sung instead of spoken.
2. Second tone, or rising tone (阳平 yángpíng, literal meaning: yang-level), or linguistically,
high-rising: is a sound that rises from mid-level tone to high (e.g., What?!)
3. Third tone (low or dipping tone, 上声 shǎngshēng or shàngshēng, literal meaning: "up tone"):
has a mid-low to low descent; if at the end of a sentence or before a pause, it is then followed
by a rising pitch. Between other tones it may simply be low.
4. Fourth tone, falling tone (去声 qùshēng, literal meaning: "away tone"), or high-falling:
features a sharp fall from high to low, and is a shorter tone, similar to curt commands.
-------From Wikipedia, the free encyclopedia
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