How can I do a program that exams the knowledge of a student ,in a way, an empty text box is shown, and he should enter the paragraph learned by heart, after that he should press a button, then if any text (letter or word) is wrong, their color will change into red, to make him know his faults. Or, may be no need to press the button, the comparison is made at once while he is typing, any thing wrong will be shown in a different text color (like red or so). How can I do that? What is the code needed? Hope you can help. Thank you in advance.