梗死是指组织细胞
A．缺氧性坏死
B．中毒性坏死
C．营养缺乏性坏死
D．因血管阻塞引起的缺血性坏死
E．感染性坏死
参考答案：D
—We were not sure which way to go. In the end we chose to turn right.
—You _______ the wrong way. You _______ left.
A．had gone; must have turned
B．went; must have turned
C．had gone; should have turned
D．went; should have turned
SARS的首发症状是（）。
A.发热
B.咳嗽
C.腹泻
D.胸闷
E.鼻塞
