Surjapuri language
Surjapuri is an Eastern Indo-Aryan language spoken in Eastern India including North Bengal, West Bengal, and Eastern Bihar, as well as in Nepal. Among speakers in some regions, it is known as 'Deshi Bhasa'. It possesses similarities with Kamatapuri, Assamese, Bengali, and Maithili. Geographical distribution. Surjapuri is mainly spoken in the parts of Purnia division (Kishanganj, Katihar, Purnia, and Araria districts) of the Mithila region of Bihar. It is also spoken in West Bengal (Uttar Dinajpur and Dakshin Dinajpur districts, and in North Malda of Malda district, specially in Harishchandrapur and Chanchal area and Siliguri city of  Darjeeling district – part of the North Bengal region within the Jalpaiguri division), as well as in parts of eastern Nepal. Related languages. Surjapuri is associated with the Kamtapuri language (and its dialects Rangpuri and Koch Rajbangshi) spoken in North Bengal and Western Assam, as well as with Assamese, Bengali, and Maithili. Pronouns. Surjapuri has the oblique plural suffixes: sā (hamsā-, tomsā-) and smā (ismā-, usmā-). They are also seen in Early Assamese as: sā (āmāsā-, tomāsā-) and sambā (esambā-, tesambā-) and their occurrences are similar. Notes. Recently, in 2021, A Sketch Grammar of Surjapuri mother tongue spoken in Bihar state  was published in Linguistic Survey of India: Bihar volume, authored by Srivastava S.P. and Perumalsamy, P and brought out by Language Division of Office of the Registrar General, India. The web publication is available in the following link: http://lsi.gov.in/MTSI_app/DraftReport/Bihar/12.%20SURJAPURI.pdf