牙内陷多见于()
A．上下颌中切牙
B．上下颌尖牙
C．上下颌第一前磨牙
D．上颌侧切牙
E．上颌第一磨牙
参考答案：D
解析： 牙内陷常见于上颌侧切牙。
I was just going to cut my rose bushes but someone _____ it. Was it you?[ ]
A. has done
B. would do
C. will do
D. had done
什么叫黄酮类化合物？主要有哪些生理功效？
