What do you think about a mind reading gadget? 

I don't know well. --> I don't know about it.  => Corrected : The sentence is corrected grammatically.

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What are you doing here? ✔​

​I'm watching the running contest.Look! -->  We're watching the race. Look over there! 

-심순이랑 얄미랑 덕보가 있어.그들은 뭐하는 중이니?  There's Simsoon, Yalmi and Dugbo.What are thry doing now? 

=> Corrected : The sentences are corrected grammatically.

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