*au, *ei, *eu, *ū → *ē, *ū, *ī, *jū, *ȳ Second palatalization: *k, *g, *x → CS *c , *dz, *ś before new *ē (from earlier *ai). *ś later splits into *š (West Slavic), *s (East/South Slavic). Progressive palatalization (or "third palatalization"): *k, *g, *x → CS *c, *dz, *ś after *i, *ī in certain circumstances. Vowel quality shifts: All pairs of long/short vowels become differentiated as well by vowel quality: a, *ā → CS *o, *a e, *ē → CS *e, *ě (originally a low-front sound but eventually raised to in most dialects, developing in divergent ways) i, *u → CS *ь, *ъ (also written *ĭ, *ŭ; lax vowels as in the English words pit, put) ī, *ū, *ȳ → CS *i, *u, *y Elimination of liquid diphthongs: Liquid diphthongs (sequences of vowel plus *l or *r, when not immediately followed by a vowel) are changed so that the syllable becomes open: or, *ol, *er, *el → *ro, *lo, *re, *le in West Slavic. or, *ol, *er, *el → *oro, *olo, *ere, *olo in East Slavic. or, *ol, *er, *el → *rā, *lā, *re, *le in South Slavic. Possibly, *ur, *ul, *ir, *il → syllabic *r, *l, *ř, *ľ (then develops in divergent ways). Development of phonemic tone and vowel length (independent of vowel quality): Complex developments (see History of accentual developments in Slavic languages). Features The Slavic languages are a relatively homogeneous family, compared with other families of Indo-European languages (e.g. Germanic, Romance, and Indo-Iranian). As late as the 10th century AD, the entire Slavic-speaking area still functioned as a single, dialectally differentiated language, termed Common Slavic. Compared with most other Indo-European languages, the Slavic languages are quite conservative, particularly in terms of morphology (the means of inflecting nouns and verbs to indicate grammatical differences). Most Slavic languages have a rich, fusional morphology that conserves much of the inflectional morphology of Proto-Indo-European. The vocabulary of the Slavic languages is also of Indo-European origin. Many of its elements, which do not find exact matches in the ancient Indo-European languages, are associated with the Balto-Slavic community. Consonants The following table shows the inventory of consonants of Late Common Slavic: 1The sound did not occur in West Slavic, where it had developed to . This inventory of sounds is quite similar to what is found in most modern Slavic languages. The extensive series of palatal consonants, along with the affricates *ts