He is an( ) boy
A. eight-years-old
B. eight-year-old
This is ( ) film that I have seen these years.
A. worst
B. worse
C. bad
D. the worst
In spring, the days are getting ( ).
A. longer and longer.
B. long and long
能影响机体的生理生化功能，用于预防、诊断、治疗疾病的物质称为什么
A. 药理学
B. 病原体
C. 药物
D. 药动学
E. 药效学
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