This is my an old ruler.哪里错了 this my old ruler只能从这几个里找

This is my an old ruler.哪里错了 this my old ruler只能从这几个里找 This is my ruler.His ruler is not an old.--------- --------- This is my an old ruler.有一处错误请指出 This is my an old ruler.改错.各位哥哥姐姐, This is my ruler,That's you ruler 这句话有错么?错在哪里? this is my a ruler不能去掉,哪里错；额 This is my yellow ruler This is my ruler.改错 This's my ruler and that's his ruler哪里错了 It is orange ruler和This is my telephone number这两句哪里错了? This is my ruler.(划线部分提问)my ruler画线 This is my ruler中的my ruler怎么提问?