Arabic ( العربي )is a name applied to the descendants of the Classical Arabic language of the 6th century AD. This includes both the literary language and varieties of Arabic spoken in a wide arc of territory stretching across the Middle East and North Africa. Some of the spoken varieties are mutually unintelligible, both written and orally, and the varieties as a whole constitute a sociolinguistic language. Arabic is the eleventh-most-spoken language in the United States. Arabic is written with the Arabic alphabet, which is an abjad script, and is written from right-to-left. Arabic has lent many words to other languages of the Islamic world, like Persian, Turkish, Somali, Bosnian, Kazakh, Bengali, Urdu, Hindi, Malay and Hausa. During the Middle Ages, Literary Arabic was a major vehicle of culture in Europe, especially in science, mathematics and philosophy. Arabic has also borrowed words from many languages, including Hebrew, Greek, Persian and Syriac in early centuries, Turkish in medieval times and contemporary European languages in modern times, mostly from English and French. Modern Standard Arabic has six pure vowels, with short /a i u/ and corresponding long vowels /aː iː uː/. There are also two diphthongs: /aj/ and /aw/. Verbs in Literary Arabic are marked for person (first, second, or third), gender, and number. They are conjugated in two major paradigms (past and non-past); two voices (active and passive); and five moods (indicative, imperative, subjunctive, jussive and energetic). There are also two participles (active and passive) and a verbal noun, but no infinitive.