长期饮酒致肝硬化机制是（）
A.引起门静脉扩张
B.直接损伤肝细胞
C.减少蛋白吸收
D.收缩肝内血管
E.阻碍胆汁流动
参考答案：B
“You'll have to wait for two hours, ________ is, at about 11：30, ________ the medical report will come out, ”the doctor said to me.
A．that; when
B．which; that
C．that; which
D．it; whose
按照满足一般项和优选项的程度，绿色建筑可划分为（）个等级。
A.二
B.三
C.四
