牙石的致病作用主要包括A.表面常可形成未钙化的菌斑 B.本身坚硬粗糙,对牙龈有机械刺 发布时间:2018-01-11 12:24 │ 来源:www.tikuol.com 题型:单项选择题 问题: 牙石的致病作用主要包括A.表面常可形成未钙化的菌斑B.本身坚硬粗糙,对牙龈有机械刺激C.多孔结构容易吸附大量的细菌毒素D.妨碍日常口腔卫生措施的实施E.以上均是
题型:单项选择题 Find out the mistakes and corract them. 找出错误并改正。( )1. Can you listen it? A B C ( )2. Why aren't dinosaurs have ears? A B C ( )3. He's teaching I English now. A B C ( )4. He hang up the phone without any words. A B C ( )5. We will meet each other in 2:00. A B C 查看答案