Here's what consonant sounds look like (the place of articulation) as
they are produced in the vocal tract.
Bilabial = two lips. Bilabial consonants are produced by creating a closure with both lips.
Labiodental = lower lip and upper teeth. Labiodental consonants are produced by raising the
lower lip to the upper teeth. English has only fricative labiodentals, and no stops.
Interdental = tongue between the teeth, or just behind the upper teeth (also called "dental"). In
English, theinterdental consonants are also all fricatives. In the ASCII phonetic alphabet, these
sounds are the voiced [th] and the voiceless [TH].
Alveolar = tongue tip at the alveolar ridge, behind the top teeth. English alveolar consonants
are formed by raising the tip of the tongue to the alveolar ridge, which lies right behind the teeth.
There are both fricatives and stops.
Note that languages differ in how related speech sounds are typically produced. For example, the
stops 't' and 'd' are alveolar in English, but in languages like Spanish, Italian and French they are
typically dental, that is, they are produced with the tongue against the back of the upper teeth (as
in todo "all" and detras "in the back of".) This gives 't' and 'd' a different characteristic sound in
these languages, and this is also one of the features that we use to identify the non-native accent in
a speaker of one of these languages who is learning English.
Palatal = the front or body of the tongue raised to the palatal region or the domed area at the
roof of your mouth. In our ASCII phonetic alphabet, these are the voiceless [S] and the voiced [Z]
Velar = the back of the tongue raised to the soft palate ("velum"), the area right behind the
palate. As with bilabials, English has a limited range of velar consonants. But these are sometimes
pronounced in words borrowed into English from languages which do have velar fricatives, e.g. from
German, Bach. The last sound below (looks like a long tail on the letter "n") is the [N] in our ASCII
phonetic alphabet.
Glottal = at the larynx (the glottis is the space between the vocal folds). Locate the glottis (the
vocal folds) in the diagram, below. A glottal stop is a speech sound articulated by a momentary,
complete closing of the glottis in the back of the throat. It exists in many languages, as in English
and Hawaiian uh-oh, O'ahu, and ka'aina.