关于膜或假膜的特点,哪项不正确()
A.纤维素等渗出物参与形成
B.剥离真膜易出血
C.假膜不易剥离
D.病原体亦参与形成
E.由脱落的结膜上皮细胞、白细胞形成
参考答案:C
She _____ your birthday party, but she had to look after her mother in hospital.
A.should attend
B.ought to have attended
C.can have attended
D.must have attended
内窥镜(用于医学切割手术)