“I didn't know that Cheshire cats always grinned; in fact, I didn't know that cats COULD grin.” “They all can,” said the Duchess; “and most of 'em do.” “I don't know of any that do,” Alice said very politely, feeling quite pleased to have got into a conversation. “You don't know much,” said the Duchess; “and that's a fact.” What is the effect of the short sentences on the dialogue? They make the dialogue smooth and serene. They make the dialogue formal and elegant. They make the dialogue into a song. They make the dialogue lively and humorous.