釉质发育不全的临床表现是()。
A.釉质表面暗白不透明、无光泽
B.釉质表面缺损呈现蜂窝状
C.釉质表面呈深度不等的带状或窝状凹陷
D.缺损处无软化现象
E.以上均是
参考答案:E
观察算式:21=2,22=4,23=8,24=16,25=32,26=64,27=128,28=256,…,….通过观察,用你所发现的规律确定的22011的末位数字是______.
Harriet is lost and her parents are really________her.
A.interested in B. afraid of C. busy with d. worried about