I believe the answer is: While the e-mail contains formal language in the body, the salutation is formatted incorrectly and the contact information is missing.
The contact information should be placed on top of the format question so the receiver know where he/she should send the reply.
Before placing salutation, it is important to address the name and position of the person who receive the salutation.
The common synonyms are usually unknown, uncertain, unclear, etc.
Singular noun is a noun that assigns to one thing, one person and one idea. Example: Boy, Girl, Father, Mother, Man, Doctor and so on.
The relationship is that well both are characters in a story for starters, and both have major parts of the story like protagonist is like the main character hero while antagonist is like the villain or bad guy so to say, so basically both encounter each other or cancel each other out like equal equal, so one side plus another, so basically like that.
