腹满时减，复如此，此为______、______。
参考答案：答案见五版讲义，从略。
A tourist will easily lose his way in Beijing ______ he has a map or a guide.
A．if
B．because
C．unless
D．when
咳嗽伴有低热、盗汗、咯血多见于（）
A.上呼吸道感染
B.胸膜炎
C.喉头水肿
D.支气管扩张
E.肺结核
