How can I use "imparfait" in the subordinate clause when the main clause is past

Question

he knew that : "I was playing football" =direct speech
he knew that I had been playing football=indirect speech
or
he knew that "I used to play football" = direct speech
he knew that I used to play football=indirect speech

How can I create "indirect speech" for these sentences
will you please help me? Thank you

Cécile Janty-Davies · Accepted Answer

Hi Ozan, 
The two tenses that don't change in indirect speech ( discours rapporté) are the imparfait and the plus que parfait.
Il savait qu'il avait joué au football = He knew that he had played football
Il savait qu'il jouait au football = He knew that he used to play football/was playing football.
Indirect speech is followed by reporting verbs like, dire, demander , répondre, raconter, expliquer etc.
savoir is not one of those.
Two sentences using the imperfect/pluperfect would be -
Il a expliqué qu'il jouait au football = He explained that he was playing football
Il a raconté qu'il avait joué au football = He said that he had played football
Hope this helps!