jespah wrote:Does be isn't proper English at all. I think I can see where you're trying to go with this, that you want emphasis. I have no problem with substituting 'really' for 'do' in the first sentence.
As for #2 - "I'm afraid it's a really good dog." Is that what you intend to say? If so, then I'm puzzled. To me, the sentence makes no sense. I realize you aren't using "I'm afraid" to mean "I'm scared" (rather, you're using it in the sense of the third definition of afraid at
www.dictionary.com, which is: "Filled with regret or concern. Used especially to soften an unpleasant statement: I'm afraid you're wrong."). But if you're using it to soften a bad situation, well, what's so bad about telling someone you have a good dog? See what I mean here?
The second sentence in fact means:
"I'm afraid (you have a prejudice against all dogs), it is really a good dog!",
but for terse purpose, the content in the parentheses has been ignored. So the usage actually fits the definition, IMHO.
Talking about "does be", the "do" here is used as an auxiliary, a means of emphasis.
For example: Do be still!
(Note: "Do be still!" actually means "You do be still!")
Thus, in logic, or in some locutions(as Kara introduced), "does be " may work.
Edit: "I'm afraid (you have a prejudice against all dogs), it is really a good dog!" should be:
"I'm afraid (you have a prejudice against all dogs
because) it is really a good dog!",
The latter is one sentence.