What is mean by concern letter?
More Definitions of Letter of concern
A letter of concern is a public document and may be used in a future disciplinary action. A letter of concern is a public document that may be used in future disciplinary proceedings.
How do you use to whom?
Whom should be used to refer to the object of a verb or preposition. When in doubt, try this simple trick: If you can replace the word with “he”' or “'she,” use who. If you can replace it with “him” or “her,” use whom.