emit

Used with why or when

• when: Named for the smelly, oily fluids they emit when alarmed.

Object

• photon: What causes an excited atom or molecule to emit a photon?
• pollutant: Not only do they use less gas, tho, they also emit fewer pollutants into the air.
• fume: We might emit some noxious fumes into the atmosphere by driving there, or leave a slight residue on a site.

Adjective complement

• infrared: Again, cloud tops are usually cooler and emit less infrared upwards than the surface, while cloud bottoms radiate some infrared back down.
• less: More than 50 Southern countries, including India, emit less than half the maximum level ( 0.2 tons per person ).

Preposition: at

• wavelength: It also shows that the black body emits at a peak wavelength, at which most of the radiant energy is emitted.