2. ManyBooks: https://manybooks.net/
3. Feedbooks: https://www.feedbooks.com/
4. Free-eBooks.net: https://www.free-ebooks.net/
5. Open Library: https://openlibrary.org/
6. Smashwords: https://www.smashwords.com/
7. BookBoon: https://bookboon.com/
8. eBook3000: http://www.ebook3000.com/
9. E-Books Directory: https://www.e-booksdirectory.com/
10. Planet eBook: https://www.planetebook.com/
11. Z-Library: https://z-lib.org/
12. Library Genesis: https://libgen.is/
13. FreeComputerBooks: https://freecomputerbooks.com/
14. GetFreeBooks: https://www.getfreeebooks.com/
15. PDF Drive: https://www.pdfdrive.com/
请注意，这些网站的免费电子书可能涉及版权问题，因此请查看每个网站的使用条款和版权信息，并在合法范围内使用它们。
