1)He said(that) he had done his work that day
2)He said(that) he had done it the previous week
3)He said(that) he was very busy then
4) He said(that) his parents lived there
5) He said(that) he often went to the theatre those days
Слово "that" можно подставить в любое из этих предложений и это не будет ошибкой. А можно оставить в прежнем виде и это так же будет верно
1)He said(that) he had done his work that day
2)He said(that) he had done it the previous week
3)He said(that) he was very busy then
4) He said(that) his parents lived there
5) He said(that) he often went to the theatre those days
Слово "that" можно подставить в любое из этих предложений и это не будет ошибкой. А можно оставить в прежнем виде и это так же будет верно