english: (Laughter) So when that happens -- this works in Keynote, PowerPoint, it works in every program -- all you do is hit the letter B key, B for blackout, to black out the slide, make everybody look at you, and then when you're ready to go on, you hit B again, and if you're really on a roll, you can hit the W key for "whiteout," and you white out the slide, and then you can hit W again to un-blank it.
non_english: Potom v Keynote, Powerpointe a každom programe, stlačte klávesu B. B ako 'blackout' na začiernenie slajdu, aby sa pozerali na Vás. Keď chcete pokračovať, stlačte znovu B. Takisto môžete stlačit W na 'whiteout', zbielenie slajdu. a potom znovu W na zobrazenie slajdu.