The Pashto language
 
Group Iranian (with Persian, Kurdish etc.), Southeast Iranian (with Pamir languages, Khwaresmian, etc.)
Geography The main literature language of Afghanistan and an important tongue in Pakistan, Pashto is spoken by 25 million people, and is divided into plenty of dialects, of which southern, western and northern groups are the widest. Pashto is developing in Afghanistan together with Dari, which has a richer literature tradition. Earlier Pashto was not used in official documents and in social and political life, but nowadays the sphere of its use is widened all the time. Active efforts are made to normalize the language and to create the single norm of literature tongue. 
History Obviously literature in Pashto existed in the Middle Ages, but the sources are not quite reliable; since the 16th century there is a firm written tradition.
Phonetics Comparing with the Pamir languages, Pashto widely uses the retroflexive consonants t., d., n., r.. A number of affricates is also great. There is a series of vowel diphthongs.
Morphology The Pashto grammar shows wide usage of inflections in verb conjugation and nominal declension, which can be either suffixed or interfixed (a suffix inside the word). The verb has a complex system of the aspect category. Ergative constructions with a declinable object are an important feature of the language. 
Writing Pashto is using the Arabic alphabet with special signs for retroflexive consonants, affricates c, dj, and some diphthongs. 
Close Contacts Pashto is closely related to Pamir languages
Sample  
Picture Palace ruins in Balkh
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