你要是在嘴里含一把牙刷，也许看上去会更有趣。
B：I'm not that stupid.
我没那么傻。
stupid /?stju?p?d; ?stu?p?d/ adj. 傻的；愚蠢的
用牙刷刷牙 brush one's teeth with a toothbrush
A：Why do you brush your teeth with a toothbrush twice a day?
为什么你一天用牙刷刷两次牙？
B：Because the dentist said it's the best way to prevent tooth decay.
因为牙医说那是防止龋齿的最好办法。
brush /br??/ v. 刷；掸；拂去
dentist /?dent?st/ n. 牙医
decay /d??ke?/ n./v. 腐烂，腐朽
◆ tooth decay 龋齿
扔掉旧牙刷 discard old toothbrushes
A：She lives a very frugal life. She's never discarded any old toothbrushes.