Maybe it is not gramatically correct but sometimes I do read sentences like: "The rat that the cat that I bought caught, ate the cheese". I am not sure if this is gramatically correct or not but since I sometimes find sentences like this I tought it could be possible. Thank you for clarifying.
"The rat that the cat that I bought caught, ate the cheese".
"The rat [ that the cat ( that I bought ) caught ] ate the cheese".
チーズを食ったネズミを捕った猫
捕ったネズミがチーズを食った猫