need some one who can help?

Question

i have an assignment in class and i spent countless hours and cannot figure this out. i refuse to give up. my problem is this... taking a number from 1 to 1000 and having the approiate two letter ending added on to it. exampl would be 191st or 293rd or 494th or 522nd I have to create an assignment to use the MOD fucntion I know that mod 5 will cause any number to give me a 1 digit now how to make cvb.net that that 1 digit apply st at ending then put original input value so i will get say, 191st. if you can handle this request please share the knowledge. for I am thirsty and need water....thanx