How can i use 'spectral line'

'energy level'

and 'electron cloud' in scientific sentences?

As an electron changes from a high energy level to a low energy level it emits a photon at a frequency associated with E=hf where E is the energy difference, h is planks constant and f is the frequency of the photon. Each photon emitted from the change in energy states is then ejected from the electron cloud in a random direction and can be noted as the atoms emission spectral line when observed.

You could search on line or in an actual book and find out what they mean,

then write a sentence with a very simple definition or explanation of each one.