I felt very tired and soon fell _____. [ ]
A. sleep
B. to sleep
C. sleeping
D. asleep
答案:D
肺结核患者发热的特点是()
A.稽留热
B.弛张热
C.间歇热
D.午后潮热
E.波浪热
写出至少四种可能引起掉话的原因和相应解决手段。