Some domains such as .com, .org, and .net can be purchased and used by any individual. However, the domain .edu is reserved for colleges and universities, while .gov denotes a government website. These two are usually credible sources for information (though occasionally a university will assign a .edu address to each of its students for personal use, in which case use caution when citing). Be careful with the domain .org, because .org is usually used by non-profit organizations which may have an agenda different than educating.
Email header: Help with grades, I have a question about my grades so on
Hello sir/madam I would like to be informed as to why my grades are so low if I have done the proper work you have presented in class. If you would be willing to help me with this after class I would be more then thankful.