学生乙临床检查时发现患者牙龈因炎症有颜色改变,无肿胀或水肿,探诊后出血,复习龈沟出血指数标准后记分为()。
A.1
B.2
C.3
D.4
E.5
参考答案:B
The Audiolingual Method develops the separation of the language skills into a ______ device, that is, listening, speaking, reading and writing.
刚结点、铰结点的特点是什么?