C# DataSet数据集内数据转化为Excel 的表格出现如图情况，求指导

应该生成两列的

                //逐行处理数据
                foreach (DataRow row in myRow)
                {
                    //当前数据写入
                    for (i = 0; i < cl; i++)
                    {
                        //if(i==(cl-1))
                        //   Is_item+=row[i].ToString()+”/n”;
                        //else
                        Is_item += row[i].ToString() + “/t”;
                    }
                    sfw.WriteLine(Is_item);
                    //sw.WriteLine(Is_item);
                    Is_item = null;
                }
求原因求指导啊！