可摘局部义齿摘戴困难的原因有:()
A.卡环过紧
B.基托紧贴牙面
C.倒凹区基托缓冲不够
D.患者没有掌握义齿摘戴方向和方法
E.基托延伸过长
参考答案:A, B, C, D
If she _____ the Great Wall next Sunday, _____ I. [ ]
A. won't visit; neither will
B. won't visit; neither won't
C. doesn't visit ; neither will
D. doesn't visit ; so won't
煤矿工人或长期吸烟者痰的颜色多为( )
A.红色 B.粉红色泡沫状 C.铁锈色 D.棕褐色 E.灰黑色