Replacing multiple characters
<p>How would I write a program, using the <code>String.Replace</code> method, that rotates the vowels in a word? Meaning the letter 'a' would be 'e', 'e' would be 'i', 'i' would be 'o', 'o' would be 'u', and finally 'u' would be 'a'.</p>

<p>For example, the word "instructor" would be "onstractur".</p>
