患者,女,42岁。颈部皮肤有7~8个细软的丝状突起,呈褐色,白行脱落后又有新的长出。其诊断是
A.寻常疣
B.传染性软疣
C.扁平疣
D.丝状疣
E.掌跖疣
参考答案:D
I used to love that film __I was a child, but I don't feel it that way any more. [ ]
A. once
B. when
C. since
D. although
活性污泥膨胀的原因有哪些?