Add the URL and you're done! URL stands for Uniform Resource Locator. That's a big fancy phrase that the computer people came up with. They tend to do that a lot. A URL is just an address on the web. You specify it like so: href="url". And since Yahoo's URL is http://www.yahoo.com/ our link ends up like so...
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Go to <a href="http://www.yahoo.com/">Yahoo!</a>
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