Besides a brain (and the knowledge of the language), what do you need to use the spoken language?
These are the speech organs.
The speech apparatus is formed by a series of organs and cavities that form a passage from the lungs to the lips and nostrils. The section of this passage that is above the larynx is called the vocal tract.
When we speak, the air we have inhaled into the lungs moves out through the trachea, the larynx and the pharynx, the nose and mouth. The sounds produced in rhis way are called egressive. Sounds produced by taking air into the vocal tract are called ingressive. Sounds in English and Spanish are egressive; certain African languages use ingressive sounds called "clicks".
We will study the speech machanism following the passage of air as we exhale, in the following sequence:
The Organs of Speech
6-velum (soft palate)
8-apex (tip) of tongue
9-blade (front) of tongue
10-dorsum (back) of tongue
You can also search more information in the following page: http://www.uiowa.edu/~acadtech/phonetics/anatomy.htm