Change the narration -
The teacher said to his students, “Do not neglect your studies”.
The teacher advised his students not to neglect their studies.
The teacher told his students not to neglect their studies.
The teacher ordered his students not to neglect their studies.
The teacher told his students that they should not neglect their studies.
Do not- যুক্ত imperative sentence দিয়ে উপদেশ বুঝালে Reporting verb advised দ্বারা replace হয়। Subject + advised + object + not + to + v1 + ext.