I always have some problem using the noun 'comment', not really sure if it has to be singular or plural. At first, I thought when a single person said something at one time, it was the singular 'comment.' But I noticed that it was not necessarily so: I've seen some people saying 'my comments', not 'my comment' for what he/she said at the time.
So when should I use the singular 'comment' and when the plural 'comments'? 

one issue/subject: comment
several issues/subjects, even in a single intervention: comments
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Would you agree with MH, everybody? 
I think informally it's usually comments. If I comment on something, I'm making comments. When someone gives their opinion, it is rare that they touch only on a single aspect of the topic being discussed. When a politician or government official issues a formal statement, that statement may be called a comment. If he does not wish to comment, he says "No comment" or "I have no comment on that".
Above are my comments on your original post.
OK. Thanks, Jim! 
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I only have one comment (to make) ..........