Labiodental Consonants

Labiodentals are consonants for which the flow of air is restricted by the lips and teeth. Labiodentals may be voiced (vocal cords vibrating during the articulation of the consonant) or voiceless (vocal cords not vibrating during the articulation of the consonant). There are two labiodentals in Present-Day English.

Examples:

/v/: 
Upper teeth: Touching the lower lip (as for (f)).
Airstream: Continuous, without interruption.
Vocal cords: Vibrating.

 
/f/: 
Upper teeth: Touching lower lip. 
Airstream: Continuous, without interruption. 
Vocal cords: Not vibrating.