We yawn when we are short of oxygen. ✬

Oxygen is needed for combustion. ✬

You can't live without oxygen. ✬

Water contains hydrogen and oxygen. ✬

Hydrogen and oxygen combine to form water. ✬

A water molecule has two hydrogen atoms and one oxygen atom. ✬

He died from lack of oxygen. ✬

A molecule of water is made up of one oxygen and two hydrogen atoms. ✬

There is almost no oxygen in the room. ✬

Tom's brain was deprived of oxygen for too long. ✬