They are usually made of wheat , barley or oatmeal , with baking powder as a leavening agent .
It is made of wheat , barley or oatmeal , usually with baking powder as leavening agent .
It is made of wheat , barley or oatmeal , usually with baking powder as leavening agent .
简化这段文字: They are usually made of wheat , barley or oatmeal , with baking powder as a leavening agent . 输出: