以下哪些原因可引起脑血管形态的改变()
A.肿瘤
B.脑血管畸形
C.动脉瘤
D.梗死
E.出血
参考答案：A, B, C, D, E
They can't get along well with each other because they have nothing____ . [ ]
A. in all
B. after all
C. in common
D. at all
结肠小袋纤毛虫滋养体借（）和分泌的（）侵入肠壁。
