下列不属于法拉卡斯托罗疾病三种传染方式的是()
A、直接接触传染
B、经媒介物传染
C、母婴传染
D、超距离传染
参考答案:C
物体做曲线运动,下列说法中正确的是
A.速度一定是变化的
B.速率一定是变化的
C.合外力一定是变化的
D.加速度一定是变化的
The joke the naughty boy _____ his teacher made many people angry. [ ]
A. made on
B. played on
C. played to
D. made to