屏幕模式
参考答案：
按照色彩混合原理中的“增色模式”混合。也就是说，对于屏幕模式，颜色具有相加效应。
— Air quality in our city is becoming worse and worse.
—Yes. These days' PM2.5 readings are frightening. We must do something to ______air pollution.
A．reduce
B．remove
C．collect
D．gather
简述我国法律关系客体的种类。
