Unknown bad habit causes tooth decay 導致蛀牙的壞習慣

Unknown bad habit causes tooth decay 導致蛀牙的壞習慣

本集內容 Unknown bad habit causes tooth decay 導致蛀牙的壞習慣

學習要點 有關“tooth decay 蛀牙”的詞匯

邊看邊答 What does Rachel do that causes damage to her teeth?

acidic

酸性的

erode

腐蝕，侵蝕

你知道嗎？ Humans have two sets of teeth. The first set of 20, which are informally referred to as ‘milk teeth’, are lost in childhood. The adult set has 32 and consists of four incisors, two canines, four premolars and six molars in each jaw.

人類有兩副牙齒。第一副20顆牙齒通常被稱為“乳牙”，在孩童時代會全部脫落。成年人有32顆牙齒，其中上下額分別都有4顆門牙，2顆犬齒，4顆前臼齒和6顆臼齒。

問題答案 Rachel holds the drink in her mouth longer than the average person, which exposes her teeth to the liquid for more time.