Emission and propagation of energy in the form of rays or waves.
发射以光线或波的形式发出和传播能量
The systematic propagation of a doctrine or cause or of information reflecting the views and interests of those people advocating such a doctrine or cause.
宣传活动对一个学说、事业或信息的系统宣传, 其反映倡导该学说或该事业的人的观点和利益
A group of organisms having common ancestors and certain distinguishable characteristics, especially a group within a species developed by artificial selection and maintained by controlled propagation.
属一群拥有共同祖先和明显特征的有机体, 尤指属于同一物种的一群, 通过人工选择来发展, 通过有控制的繁殖来维持
