Provide two written definitions of an oxidation-reduction reaction

Oxidation is the loss of electrons while reduction is the gain of electrons. Oxidation is the addition of oxygen while reduction is the removal of oxygen.

Explanation:

Oxidation and reduction can be defined in different ways. The common ways are

1) in terms of addition or removal of electrons

2) in terms of addition or removal of oxygen

3) in terms of addition or removal of hydrogen

4) in terms of increase or decrease in oxidation number.

All definitions are valid but their individual applications are context dependent.