肿瘤形成原因包括______
A．化学性
B．物理性
C．生物性致癌因素
D．机体抗肿瘤能力降低
E．年龄、遗传因素
参考答案：A,B,C,D,E
The core of ______ is language acquisition which is considered a subconscious process, dependent on the amount of input the students get and allow in.
A．The Direct Method
B．The Audiolingual Method
C．The Cognitive Approach
D．The Natural Approach
岩心管提出孔口后，可以用手摸或眼看管内岩心。
