YOU SAID:

my friend sit on a chair working on a test so dont bother him

INTO JAPANESE

私の友人は椅子に座ってテストをしていますので、彼を気にしません

BACK INTO ENGLISH

My friend sits on a chair and is testing, so I do not mind him

INTO JAPANESE

私の友人は椅子に座ってテストしているので、私は彼に気にしない

BACK INTO ENGLISH

I do not mind him because my friend is sitting in a chair and testing

INTO JAPANESE

私の友人は椅子に座ってテストしているので私は彼に気にしない

BACK INTO ENGLISH

I do not mind him because my friend is sitting in a chair and testing