我们知道,经常锻炼有利于增强体质,有利于提高抗传染病的能力,从免疫的角度看体育锻炼应属于[ ]
A.控制传染源
B.切断传播途径
C.保护易感人群
D.以上全对
答案:C
.Jim gave us ______ on how to learn English well.[ ]
A. some advices
B. many advices
C. some advice
D. an advice
下列各项,属五行之土者为
A.酸 B.苦 C.甘 D.辛