If you are using Google chrome, please have try on Google Dictionary:
https://chrome.google.com/extensions/detail/mgijmajocgfcbeboacabfgobmjgjcoja?hl=en-USBelow image can be used to show the basic function of Google Dictionary:
acceptable /æks'eptəbəl/
Once you click More, you can see the word's details. And you can mark one star by click the star ahead of the word. Very cool!
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