I'd use one of these – assuming that Monday is only a few days away:
She will be on leave this Monday.
She will be on leave on Monday.
She will be on leave this coming Monday.
Rover
She will be on leave on this Monday. (I am talking about the leave which means absent or holiday and leave, left)
Is this sentence correct and natural?
I'd use one of these – assuming that Monday is only a few days away:
She will be on leave this Monday.
She will be on leave on Monday.
She will be on leave this coming Monday.
Rover
You will hear the present tense used here though.
- I'm going to arrange a meeting with Jane on Monday.
- Don't bother. She's on leave that day.
- Why do you look so excited?
- Because I'm on leave next week!! Hurrah!!
Remember - correct capitalisation, punctuation and spacing make posts much easier to read.