Question

indirect speech of the teacher said to the boy," why were you absent yesterday?"

Answer 1

Heya
Here is your answer
_____________________________________________________________

The teacher asked the boy why he had been absent the previous day

were/was is changed into had been
why is a question word so it is not changed into if or whether
yesterday is changed into the previous day or the day before
persons are changed according to SON rule
asked is used instead of told etc. in interrogative substances
____________________________________________________________

Hope this helps! ^_^

Answer 2

Answer:the teacher asked boy why was he absent the previous day

Explanation:in some sentences tenses rule is not applied