To copy the text in the PDF-file, you need to use some specialized PDF-editing software. For example, you can use Adobe Acrobat Pro or other PDF-editing software to convert a PDF-file to a text file or use some online PDF-editing tools to convert a PDF-file directly to a text file. The method of converting text files may vary depending on the software used. The usual steps to convert a PDF-file to a text file include: 1 Open the PDF-editing software and select the "Save as a text file" option in the "file" menu. 2 When saving as a text file, you need to choose to save the file to the specified disk and specify the file name and file type. 3 After the conversion, you can save the text file to your local computer. Another way is to use some online PDF-editing tools, which are usually available directly in the browser. For example, you can use Google Docs or Google Word to convert a PDF-file into a text file. When converting, you can choose to convert the PDF-file to a plain text file or convert the PDF-file to an browser file for viewing. Regardless of which method you use, you need to pay attention to the security of the PDF-file. You should choose professional software or tools when converting to PDF-files and ensure that the file is fully protected to prevent malicious attacks or tamper with the file.