He makes a good point, though perhaps a bit unclear. Interrogative verbs can sometimes form a little definitely.
In his example, you would say "He does (do) the mambo." But the question is "What does he do?" Think of it this way: The "does" part is understood, and so acts as the main verb, turning the other verb into a helping verb (generally formed with the infinitive without the "to").
What does ok stand for? It (does) stand for something.
Hope that helps!
Tommy Wallach | Manhattan GMAT Instructor | San Francisco
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