美国英语与中文的不同。发音方面的。

Mandarin Chinese may sound strange, but is actually relatively easy for English-speakers to pick up—much easier than it is for Mandarin-speakers to learn English. A large part of the reason is that Chinese has a very limited sound inventory, meaning there are not many sounds in the language, and hardly any new ones if you already know English. On the other hand,Chinese-speakers trying to grasp English must learn to create dozens of entirely new sounds.

One very different aspect of Chinese is its use of tones. Because of its limited inventory, pitches of voice are used to help differentiate words. While some dialects of Chinese have up to nine tones, Mandarin is comparatively easy with only four.

It's often difficult to distinguish the tone of a word, especially when not sure of the context. Even if you have perfect pitch, it may be hard to follow or reproduce what can seem like a rollercoaster ride of tonal transitions.

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