The dog temporarily refrained from sniffing around the floor of the kitchen, looked up at the man and said, "The crux of the biscuit is the apostrophe."
The man that was talking to the dog looked at the dog and said, staring in somewhat aberrant disbelief, "You can't say that!" The man proceeded with a succession of contractions. "You can't, it doesn't, I won't, it hasn't it isn't, it even ain't, it couldn't, it wouldn't, it shouldn't."
The dog smiled and wagged his tail. "Of course it can. It does, you will, it has, it is, it could, it would, and it shall. I do it all of the time."
After several moments of what would appear to be a staring contest between the man and the dog, the dog said, "Would you like to come with me next time?"
The man replied, "I thought you'd never ask!"