Tone Practice

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* My suggestion *

1. Standardize each tone while doing pronunciation. (e.g. Let your second tone always a rising one, your third tone always a low one.)
   
2. Feel each tone. (Make it seem like there's a sound template saved in your mental database.)
   
3. Apply the feeling on new words having the same combination of tones. (Your "new friend" also has something in common with your "old friend."----either in meaning, or in sound.)