The normal phrase is "You are correct," or, more formally, "You're correct"—perhaps the speaker is saying the latter but the "re" is muted by his or her voice or accent. This is called "syntax." When you write correctly, you use correct grammar and punctuation to create a clear sentence that doesn't sound like nonsense. When you write how do you write correctly, this means that you should follow some basic guidelines when you draft an email or other document. These include using proper spelling, grammar, and punctuation; choosing relevant language; avoiding slang words or phrases; and being aware of your audience when you write. For example, if you were writing something that was supposed to be read by someone who didn't know you very well, you would probably want to use simple language and avoid colloquialisms. You would also want to be sure to choose your words carefully and not say anything that could be interpreted as insulting or offensive. As another example, if you were writing something that was going to be shown to someone who did not know you well, but who had seen pictures of you before, you might want to use a formal tone when writing about yourself in the third person.