The first section of the mouth is known as the oral cavity, or the mouth cavity. This space is bordered in the front and to the sides by the two alveolar arches, which contain the teeth. Toward the back it is bordered by the isthmus of the fauces. This entire structure is also called the mouth; the structures within the mouth allow us to taste and masticate (chew) food, to swallow food and drink, and to manipulate the air that comes up from the voice box so that we can form words.