copy in duplicate

例句：

1. 1.Please make sure to copy the important documents in duplicate before you leave.
   在你离开之前，请确保将重要文件复制两份。
2. 2. The company has just issued a new product, and I need to copy it in duplicate for my presentation.
   公司刚刚发布了新产品，我需要将它复制两份用于我的演示。
3. 3. The teacher asked us to copy the text in duplicate so that we could compare them later.
   老师要求我们将文本复制两份以便以后进行比较。