Question

change into indirect speech "Do not tell a lie", said the teacher.

Answer 1

Teacher said that dont tell a lie.

I hoped these W ill helps u

Answer 2

The teacher told the student not to tell a lie. In a direct speech, the quotations are there and whatever the speaker utters is told inside quotations.

In indirect speech however, the speech is reported as part of the speech that is reported indirectly.  Generally in indirect speech, the content of the statement is represented as part of a reported speech.