支气管内插管的绝对适应证有哪些？
参考答案：①肺脓肿；②支气管扩张痰量多；③肺大泡有明显液面的病人；④支气管胸膜瘘；⑤大咯血。
下列叙述中，不属于面向对象方法的优点的是______。
A．可重用性好
B．与人类习惯的思维方法一致
C．可维护性好
D．有助于实现自顶向下、逐步求精
We didn't know you were in trouble at that time, otherwise we________ you a hand. [ ]
A. had given
B. gave
C. would give
D. would have given
