同一时间能把握的对象数量称为()。
A．注意的时间
B．注意的稳定性
C．注意的广度
D．注意的转移能力
参考答案：C
有机肥是土壤()的重要来源。
A、胶体
B、腐殖质
C、盐分
D、速效养分
In the opinion of Li Ming, a science student in that high school, physics is_______ chemistry, but much easier than English.
A．as difficult a subject as
B．as a difficult subject as
C．a subject so difficult as
D．difficult as a subject as
