听力原文:W: May I speak to Mr. Li? M: Which Li, ma'am? There are two Lis here. W: Oh? Mr. Li, head of the Export Section. M: Oh, the chief? That's Mr. Michael Li, then. W: Is that right? M: I'm sorry, but Mr. Li's gone on a trip. W: I see. When will he return? M: He'll be back next Monday. W: All right. I'll call on Monday again. M: May I have your name? W: Mrs. Dorothy Preston. M: Mrs. Dorothy Preston. Is that Dorothy with a 'y'? W: That's right. M: I'll tell Mr. Li you called when he returns. W: Thank you. Where is Mr. Li?