emit ·verb
Definition: to send out gas, heat, light, etc. into the air Level: C2
当你按下按钮时，机器会发出高音调的声音。
The machine ___emits a high-pitched sound when you press the button.
所有车辆和工厂排放烟雾，这些烟雾会导致严重疾病，如癌症。
All the vehicles and factories ___emit fumes, which cause grave diseases such as cancer.
科学家测量恒星发射的红外辐射以确定其温度。
Scientists measure the infrared radiation that stars ___emit to determine their temperature.