(03/25/21)

-그녀는 핸드폰이 없어.

She doesn't have her smartphone. -> She doesn't have a cell phone. 

-내가 머무르길 바라니?

 Do you want me to stay? ​

-수업 언제 끝나?

 When does your class finish? -> When do you finish your class?

=> Your sentence has a correct grammatical structure, but this has the correct usage/ expression.

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