known. Hadza is noted for having medial clicks (clicks within morphemes). This distribution is also found in Sandawe and the Nguni Bantu languages, but not in the Khoisan languages of southern Africa. Some of these words are historically derivable from clicks in initial positions (many appear to reflect lexicalized reduplication, for example, and some are due to prefixes), but others are opaque. As in Sandawe, most medial clicks are glottalized, but not all: puche 'a spleen', tanche 'to aim', tacce 'a belt', minca 'to lick one's lips', laqo 'to trip someone', keqhe-na 'slow', penqhenqhe ~ peqeqhe 'to hurry', haqqa-ko 'a stone', shenqe 'to peer over', exekeke 'to listen', naxhi 'to be crowded', khaxxe 'to jump', binxo 'to carry kills under one's belt'. Tone Neither lexical tone nor pitch accent has been demonstrated for Hadza. There are no known lexical minimal pairs or grammatical use of stress/tone. Vowels Hadza has five vowels, . Long vowels may occur when intervocalic is elided. For example, or 'to climb', but some words are not attested with , as 'she' vs 'to be ill'. All vowels are nasalized before glottalized nasal and voiced nasal clicks, and speakers vary on whether they hear them as nasal vowels or as VN sequences. Invariable nasal vowels, although uncommon, do occur, though not before consonants that have a place of articulation to assimilate to. In such positions, and are allophones, but since VN cannot occur at the end of a word or before a glottal consonant, where only nasal vowels are found, it may be that nasal vowels are allophonic with VN in all positions. Consonants The nasalization of the glottalized nasal clicks is apparent on preceding vowels, but not during the hold of the click itself, which is silent due to simultaneous glottal closure. The labial (or ) is found in a single mimetic word where it alternates with . The labial ejective is only found in a few words. The palatal affricates may be pronounced with an alveolar onset ( etc.), but this is not required. The velar ejective varies between a plosive , a central affricate , a lateral affricate , and a fricative . The other central ejective affricates can surface as ejective fricatives as well (i.e. ). The lateral approximant is found as a flap between vowels and occasionally elsewhere, especially in rapid speech. is most common post-pausa and in repeated syllables (e.g. in