Although much of the practical work in HCI revolves around the design of graphical user interfaces, HCI is concerned with a number of topics, including
... th, d, dh, n)
Dental (tongue against teeth, like Spanish) (t, th, d, dh, n)
Labial (with the lips[?]) (p, ph, b, bh, m)
It also has four semivowels: y, r, l, v. ...