in weak position developed as if strong to avoid overly awkward consonant clusters: Proto-Slavic "stem, stalk" > (stebló) (cf. Old Czech , Czech or (dialectal) , Old Polish or , Polish , all meaning "stalk, straw") Proto-Slavic "variegated" > (pjóstryj) (cf. Polish , but Czech ) Proto-Slavic "to ring, to clank" > (zvenétʹ) (cf. Old Czech , Czech ) As shown, Czech and especially Polish are more tolerant of consonant clusters than Russian; but Russian is still more tolerant than Serbo-Croatian or Bulgarian: Proto-Slavic "mist, haze" > (mgla) (cf. Old Czech , Polish , but Serbo-Croatian , Bulgarian (măglá) ). Loss of nasal vowels The nasal vowels (spelled in the Cyrillic alphabet with yuses), which had developed from Common Slavic and before a consonant, were replaced with nonnasalized vowels: Proto-Slavic > Russian u Proto-Slavic > Russian ja (i.e. with palatalization or softening of the preceding consonant) Examples: PIE "they are" > Proto-Slavic > (sutʹ) (literary in modern Russian; cf. Old Church Slavonic (sǫtĭ), Polish , Latin ) Proto-Slavic "hand" > Russian (ruká) (cf. Polish , Lithuanian ) Proto-Slavic "meat" > Russian (mjáso) (cf. Polish , Old Church Slavonic (męso), Old Prussian mensa, Gothic (mims), Sanskrit (māṃsa)) PIE "five" >> Proto-Slavic > Russian (pjátʹ) (cf. Polish , Old Church Slavonic (pętĭ), Lithuanian , Ancient Greek (pénte), Sanskrit (páñcan)) In the case of Proto-Slavic > Russian ja, the palatalization of the preceding consonant was due to the general Russian palatalization before all front vowels, which occurred prior to the lowering of to . If the preceding consonant was already soft, no additional palatalization occurred, and the result is written rather than when following the palatal consonants (š ž č šč c): Proto-Slavic "to begin" > Russian (načatʹ) (cf. Old Church Slavonic (načęti)) Proto-Slavic "harvest" > Russian (žátva) (cf. Old Church Slavonic (žętva)) Nearly all occurrences of Russian (ja) following a consonant other than (l), (n) or (r) are due to nasal vowels or are recent borrowings. Borrowings in the Uralic languages with interpolated after Common Slavonic nasal vowels have been taken to indicate that the nasal vowels existed in East Slavic until some time possibly just before the historical period. Loss of prosodic distinctions In earlier Common Slavic, vowel length was allophonic, an automatic concomitant to vowel quality, with short and all other vowels (including nasal vowels) long. By the end of the Common Slavic period, however, various sound changes (e.g. pre-tonic