Check out the new tone trainer feature!
Dong Chinese Tone trainer

This tools helps to practice differentiating the tones.

You can choose between single-syllable words, or two-syllable words. There is actually a fairly big jump in difficulty between hearing tones in isolation and hearing two tones together in a single word. When I tested it on my wife (who is learning Chinese), I was a bit surprised that she was able to recognize the tones in single-syllable words perfectly, but she had a lot of difficulty with two syllable words.

You can use the checkboxes to choose which tones you want to practice. For example, if you are specifically having trouble differentiating the 2nd and 3rd tones, you can choose those ones and the test will only include words with those tones.

Also, if you like zhuyin more than pinyin, you can try out the zhuyin version of the tone trainer.

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