How to pass correct html select value to $_POST php

I have tried html like this:

<form method="post">
   <select id="select" size="2 ">
        <option value="3">test</option>
        <option value="4">test2</option>                     
   </select>
   <button type="submit" value="execute">
</form>

How do I get a 3 or 4 value in the post array

$_POST['select']
开发者_如何学运维

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Add the name tag...

<select id="select" name="select" size="2 ">