Paradigms with mobile vowel length/shortness do exist but only in a limited fashion, usually only with the zero-ending forms (nom. sg., acc. sg., and/or gen. pl., depending on inflectional class) having a different length from the other forms. (Czech has a couple of other "mobile" patterns, but they are rare and can usually be substituted with one of the "normal" mobile patterns or a non-mobile pattern.) Old Polish had a system very much like Czech. Modern Polish has lost vowel length, but some former short-long pairs have become distinguished by quality (e.g. > ), with the result that some words have vowel-quality changes that exactly mirror the mobile-length patterns in Czech and Slovak. Grammar Similarly, Slavic languages have extensive morphophonemic alternations in their derivational and inflectional morphology, including between velar and postalveolar consonants, front and back vowels, and a vowel and no vowel. Selected cognates The following is a very brief selection of cognates in basic vocabulary across the Slavic language family, which may serve to give an idea of the sound changes involved. This is not a list of translations: cognates have a common origin, but their meaning may be shifted and loanwords may have replaced them. Influence on neighboring languages Most languages of the former Soviet Union and of some neighbouring countries (for example, Mongolian) are significantly influenced by Russian, especially in vocabulary. The Romanian, Albanian, and Hungarian languages show the influence of the neighboring Slavic nations, especially in vocabulary pertaining to urban life, agriculture, and crafts and trade—the major cultural innovations at times of limited long-range cultural contact. In each one of these languages, Slavic lexical borrowings represent at least 15% of the total vocabulary. This is potentially because Slavic tribes crossed and partially settled the territories inhabited by ancient Illyrians and Vlachs on their way to the Balkans. Germanic languages Max Vasmer, a specialist in Slavic etymology, has claimed that there were no Slavic loans into Proto-Germanic. However, there are isolated Slavic loans (mostly recent) into other Germanic languages. For example, the word for "border" (in modern German , Dutch ) was borrowed from the Common Slavic . There are, however, many cities and villages of Slavic origin in Eastern Germany, the largest of which are Berlin, Leipzig and Dresden. English derives quark (a kind of cheese and subatomic particle) from the German , which in turn is derived from the Slavic , which means "curd".