every thing in earth is a substance. is the sound and light wave a substance?
It really depends on what you mean as a substance. Through a complicated series of equasions which I cannot remember it can be proven that photons have mass. If this is true then they are indeed a substance. Sound waves are made by a series of collissions with the molecules in the air. The wave itself is not a substance it is energy being transmitted through a medium(air molecules). The pressure differences caused by this transmission hit your ear and you sense the sound being emitted. So, the waves themselves are not really a substance the waves are a transmission of energy. However they are both made up of substances.
