Which one is grammatically correct?
My mind is not yet at ease with that.
My mind is not yet at ease about that.
My mind is not yet at ease over that.

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Answer

The answers are in "keys to words"!  You are having trouble with the small common words.  "keys to words" is the answer.  http://www.keys2words.info/

I like your questions

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WITH

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i don't think so...From the mean of your examples,i have my answer like this: 
"My mind has not eased about that yet" 
(Notes:This should be used in the present perfect to mention the result that still related in the present;and the adverb"yet" is often used in the end of a question or a native sentence.)

Answer

first one. :)

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