You'll find this chart and some explanation on page 6 of Kelly's How to Teach Pronunciation


1. alveolar

d. the blade of the tongue is used close to the alveolar ridge
2. glottal

e. the gap between the vocal cords is used to make audible friction
3. dental

a. the tongue tip is used either between the teeth or close to the upper teeth
4. palato-alveolar

g. the blade of the tongue is used just behind the alveolar ridge
5. bilabial

h. using closing movement of both lips
6. velar

b. the back of the tongue is used against the soft palate
7. palatal

f. the front of the tongue is raised close to the palate
8. labio-dental

c. using the lower lip and the upper teeth