She has lived here()three years.
A.since
B.for
C.during
D.in
参考答案:B
内痔便血的特点是()
A.黏液脓血便
B.大便带血,颜色鲜红
C.板油样便
D.水样便
E.羊粪样便
目前戊肝病毒有()个血清型。