abkhaz language acoustics affricate consonant alveolar consonant alveolo-palatal consonant amplitude apical consonant approximant consonant articulation auditory basque language click consonant consonant dental consonant ejective consonant english language frequency fricative consonant ian maddieson implosive consonant international phonetic alphabet laminal consonant lateral consonant liquid consonant manner of articulation morris halle nasal consonant noam chomsky northwest caucasian languages obstruent palatalization peter ladefoged polish language postalveolar consonant retroflex consonant russian language secondary articulation semivowel shandong shona language sonorant sound intensity stop consonant strident vowel toda language trill consonant ubykh language vocal tract voiced labiodental fricative voiceless labiodental fricative vowel whistling