常难以入睡、睡眠中多醒或早醒( )
A．睡眠性呼吸暂停B．睡眠过度C．发作性睡眠D．梦游症E．原发性失眠症
参考答案：E
Studies show the MP3 people have made much use of ______ music may be causing hearing loss in many people.
A．enjoy
B．to enjoy
C．enjoying
D．enjoyed
注入水对油井造成的损害主要是（）、（）、（）三大类。
