有一天一位母亲带着她的儿子去拔牙，因为她的儿子牙痛的非常厉害。这名牙医

One day a mother took her son to have her teeth extracted because her son had a severe toothache. The dentist offered a price of four dollars, and the mother agreed. However, when the tooth was extracted, the dentist changed his mind and offered to pay $20. <br>"20 dollars! You liar! You said 4 dollars before!" The mother said <br>that the dentist explained, "Because your son's scream scared away many of my patients

One day a mother took her son to pull out her teeth because her son had a terrible toothache. The dentist offered four dollars, and the mother agreed. But when the tooth was pulled out, the dentist changed his mind and offered $20.<br>"$20! You liar! You're talking about $4 before you know it! The mother said<br>The dentist explained, "Because your son's screams scared away many of my patients.

One day, a mother took her son to have a tooth extracted because her son had a terrible toothache. The dentist offered four dollars, and the mother agreed. But after the extraction, the dentist changed his mind and asked for $20.<br>"Twenty dollars! You liar! You said four dollars before! Said the mother<br>The dentist explained, "because your son's screams scared away a lot of my patients<br>