She quickly discovered that the local Khmer dialect was different from the one she grew up speaking, so early conversations were often unintelligible for both sides.

The Khmer script is especially demanding, with 68 vowels and consonants; students usually need about a year and a half to master the alphabet and roughly three years to read and write fluently.

According to the Tay Ninh Department of Education and Training, only three primary schools—Phuoc Vinh, Tan Phu and Binh Minh—offer Khmer classes, serving a total of 266 students with just three teachers.

Ca Di uses digital lesson plans, videos and bilingual recordings to help learners overcome the script’s difficulty, and after several years her students, such as 11th‑grader Khe Thi Sieng, have become fluent.

She says, “Every child who learns to read and write Khmer helps preserve a piece of ethnic culture for the next generation,” echoing the view that teaching the language is essential for cultural heritage.