哮喘的治疗原则是（）。
A.长期
B.持续
C.规范
D.个体化
参考答案：A, B, C, D
______ readers said they were going to learn a new language. [ ]
A. A little
B. Little
C. Few
D. A few
熔池中（）最先出现晶核。
A．焊趾上
B．焊根部
C．热影响区
D．熔合线上
