How many atoms can be reduced in a single redox reaction? I am doing high school chemistry and I am busy working with redox reactions.

The explanation in my text book, of how a redox reaction works, left me a bit confused as to how many atoms can be reduced/oxidized in a single reaction equation. 

Can only one atom (species) be reduced/oxidized in a single equation or can there be more than one reduced/oxidized in the same chemical equation?

All of the reaction equations I have come across so far have just one atom reduced and one atom oxidized, for example:

$$ \ce {Mg(s) + 2HCl(aq) -&gt; H_2(g) + MgCl_2(aq)} $$

In this reaction only Mg is oxidized and only H is reduced. Is there a reaction in which more than one species of atom it reduced or oxidized?
I'm not sure if I understand your question correctly, but consider the reaction

$$\ce{CH3-SH + 3 O2 -&gt; SO2 + CO2 + 2 H2O}$$

where methanethiol is oxidized with oxygen to sulfur dioxide, carbon dioxide, and water.

Thereby the oxidation states of sulfur and carbon change from $-2$ to $+4$ and the oxidation state of oxygen from $\pm0$ to $-2$. So sulfur and carbon atoms are both oxidized while oxygen is reduced.

I hope this answers your question.