I need help making a YouTube poop with wmv. This will only take you like one minute?

I'm making an Arthur poop. How do I make Arthur say something innapropiate without him going back to what he was suppose to say so quickly. Like ifi want him to say "hi Buster after school you wanna SH!T together" basically I need him to give it enough time to say SH!T before he continues with his regular conversation. I want to drag the video on the time line just enough so he can have to but I don't know how. Can someone please help me??? And invade you don't know what I'm talking about: I just need the characters to give me enough time to put in a bad word before they start back talking and interrupting it. Thx and srry it's so long I just want you to know the problem well