直肠腺瘤有：（）
A．管状腺瘤
B．管状绒毛状腺瘤
C．不典型增生性腺瘤
D．绒毛状腺瘤
E．息肉性腺瘤
参考答案：A,B,D
—I am sorry to have __ too much of your time.
—That's OK, and I am glad to help you. [ ]
A. taken up
B. taken on
C. taken off
D. taken in
三相异步电动机的旋转磁场是怎样产生的？
