"We discussed the issue [absence of training] with the primary education ministry and the NCTB," the education official said, adding they were yet to receive any instructions from the higher authorities in this regard.

Against this backdrop, teachers in classrooms prioritise Bangla textbooks over the ones written in ethnic languages for imparting lessons, throwing the whole idea of mother tongue-based education in question.

Sunali Deb Barma, a student of class two at Daluchhara Government Primary School in Moulvibazar's Sreemangal upazila, told our Moulvibazar correspondent that they received their books in Tripura language at the beginning of the new year, but no class has been taken yet using these books.

Moreover, there is no clear instruction for teachers on how to impart lessons in a class where there are students from more than one community.

"When we take classes of Marma and Chakma students, Tripura students find nothing to do, and therefore loiter around during that period," said a Chakma teacher at a Khagrachhari school.

Experts say establishing mother tongue-based education at the primary level is not only limited to distributing books.

"It also requires proper training for the teachers and guidelines regarding the teaching method as multilingual teaching system is different from traditional teaching," said Prof Sourav Shikder, a teacher at Dhaka University's linguistics department.

He suggested that the teachers be given a minimum three months of training.

Rabindranath Soren, president of Jatiya Adibasi Parishad, said ensuring proper training is necessary for ensuring the quality of the teaching.

"Besides, we need to keep our languages alive," he added.