four tones

基本解释

Its vowels include plain, pharyngealised, strident and breathy, and they carry four tones.
元音包括简单音，咽音，刺耳音，气音，而且有四个声调。
The "slowest" language, Mandarin, partly thanks to the four tones, has around 2000 possible syllables, far more than Japanese or Spanish.
语速最慢的汉语普通话有大约2000个音节，比日语和西班牙语多得多。有四个音调也是普通话语速慢的部分原因。
Not only do foreigners find it difficult to master the four tones of Mandarin, but the alien grammar and the difficulty of rote-learning thousands of words overcome all but the most diligent students.
外国人不但觉得汉语中的四声调很难掌握，而且那些陌生的语法和死记硬背的成千上万的汉字也让他们头疼，似乎只有最勤奋的学生才学得会。

Then students have the daunting task of learning to pronounce Mandarin, where one word can have four meanings, depending on which of four tones is used.
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