how is its characteristics?
An area of great difference among Slavic languages is that of prosody (i.e. syllabic distinctions such as vowel length, accent, and tone). Common Slavic had a complex system of prosody, inherited with little change from Proto-Indo-European.
Slavic languages
An area of great difference among Slavic languages is that of prosody (i.e. syllabic distinctions such as vowel length, accent, and tone). Common Slavic had a complex system of prosody, inherited with little change from Proto-Indo-European. This consisted of phonemic vowel length and a free, mobile pitch accent:

The modern languages vary greatly in the extent to which they preserve this system. On one extreme, Serbo-Croatian preserves the system nearly unchanged (even more so in the conservative Chakavian dialect); on the other, Macedonian has basically lost the system in its entirety. Between them are found numerous variations:
who would call the sea of japan the east sea South Korea where is this sea? It is bordered by Japan, Korea (North and South) and Russia. where did the last mentioned place take its name from? The name "Russia" is derived from Rus', a medieval state populated mostly by the East Slavs. who are there people you mentioned at the end? The East Slavs are Slavic peoples speaking the East Slavic languages. how are they sourced? The few known facts come from archaeological digs, foreign travellers' accounts of the Rus' land, and linguistic comparative analyses of Slavic languages what are these languages? The Slavic languages, also known as the Slavonic languages, are Indo-European languages spoken primarily by the Slavic peoples or their descendants. how did it evolve? In the 19th century, Russian influenced most literary Slavic languages by one means or another. what are its divisions? The Slavic languages are a relatively homogeneous family, compared with other families of Indo-European languages. As late as the 10th century AD, the entire Slavic-speaking area still functioned as a single, dialectally differentiated language, termed "Common Slavic".
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Slavic languages [SEP] Length, accent, and tone
An area of great difference among Slavic languages is that of prosody (i.e. syllabic distinctions such as vowel length, accent, and tone). Common Slavic had a complex system of prosody, inherited with little change from Proto-Indo-European. This consisted of phonemic vowel length and a free, mobile pitch accent: The modern languages vary greatly in the extent to which they preserve this system. On one extreme, Serbo-Croatian preserves the system nearly unchanged (even more so in the conservative Chakavian dialect); on the other, Macedonian has basically lost the system in its entirety. Between them are found numerous variations: