下列"结肠癌"的造影表现，哪项也可见于良性病变（）
A.环堤
B.半月征
C.结肠壁局限性僵硬
D.苹果核征
E.充盈缺损
参考答案：E
阅读对话，完成句子。
John: Hello.
Bill: Hello. It's Uncle Bill. Is everybody at home?
John: Yes.
Bill: What are they doing?
John: Grandma is writing. Dad is writing an e-mail. Mom is washing the clothes. And I am sweeping the floor.
1. _______________ is _________________________.
2. _______________ is _________________________.
_______________ is _________________________.
_______________ is _________________________.