I have been living in the United States for twenty years, but seldom _____ so lonely as

now. [ ]

A. have I felt

B. I had felt

C. I have felt

D. had I felt

下列哪些不是颅内压增高者的呕吐特点（）

A.常为喷射状

B.多在头痛剧烈时出现

C.常与饮食有关

D.常为严重颅内高压唯一早期症状

E.幕下肿瘤者发生率较高