Czech vocabulary comes mostly from Slavic, Baltic and other Indo-European roots. Most loanwords in Czech come from German, Greek and Latin. In recent times, loanwords from a wider variety of languages have arrived, principally English and French. Some Czech words have been adopted as loanwords into English and other languages, e.g. robot and polka.
Czech nouns, verbs and adjectives are inflected by phonological processes to modify their meanings and grammatical functions. In Czech, inflection is particularly complex and pervasive, inflecting for many categories such as case, gender and number of nouns and tenses, aspect, mood and person, and number and gender of the grammatical subject in verbs. Negative statements are generally formed simply by adding the prefix ne- to the verb.
Czech has one of the most phonetic and regular orthographies of all European languages: its thirty-one graphemes represent thirty sounds and it contains only one digraph, ch, which follows h in the alphabet. The hacek (ˇ) is used with certain letters to form new characters: š, ž and č, as well as ň, ě, ř, ť and ď, which are uncommon outside Czech. Unlike most European languages, Czech distinguishes vowel length: long vowels are indicated by an acute accent while short vowels are left unaccented. Another unusual feature is that in proper noun phrases with more than one word, only the first word is capitalized, for example, Pražský hrad (Prague Castle). This rule does not apply to personal or geographic names.