A、<img alt="说明:01" src="http://admintk.100xuexi.com/UpLoadImage/2013-05-07/f0175436-059d-42e9-bcad-ee224462ebc6.jpg" width="14" height="14" />面长方形，有五条发育沟
B、舌面外形高点在<img alt="说明:01" src="http://admintk.100xuexi.com/UpLoadImage/2013-05-07/f0175436-059d-42e9-bcad-ee224462ebc6.jpg" width="14" height="14" />1/3处
C、邻面外形高点在颈1/3处
D、颊面似长方形，有两个牙尖
E、有两颊一舌3个牙根