短文改错/Proofreading and error correction

It was the chance of a lifetime to win the first prize on the Story Writing Show. All I had to do was to write a story or present it. My teachers have been telling me how great my writing was. So if they had said was true, I would have a chance of winning the prize. What were better, I had useful help. There was Uncle Chen, gentleman living near my house, who was a very much famous writer. He agreed to reading my story and give me some advices on how to write like a real writer.

7（）

企业发出各种材料应负担的成本差异可按当月材料成本差异率计算，若发出的材料在发出时就要确定其实际成本，则可按上月材料成本差异率计算。（）