Answer:
            In a reduction half-reaction the number of electrons an element gains are shown.
Explanation:
                   Reduction reactions are those reactions in which an atom gains electron (s). In a cell a redox reaction is carried out either utilize electricity or produce electricity. Let suppose a general redox reaction shown below,
                                  A⁺  +  B      →      A  +  B⁺
For above reaction the reduction half-reaction is as follow,
                                 A⁺  +  1 e⁻     →      A
(Hence, in this reaction only the number of electrons an element gain are shown)
And the oxidation half reaction is as follow,
                                B      →       B⁺  +  1 e⁻