句中的"rate the books you've read, leave reviews, and connect with other readers"和LibraryThing部分的最后一句中的"Behind its book ratings and reviews though"可知，Goodreads和LibraryThing都要求读者评价并留下书评，故选D。

　　2．Which book recommendation site can help you get super­low cost books?

　　A．Goodreads.　　B．BookBub.

　　C．LibraryThing. D．Olmenta.

　　答案与解析：B　考查细节理解。根据BookBub部分的第一句"While BookBub isn't strictly a book recommendation site, it does bring you super­low cost books based on your interests every day"可知，BookBub这个网站可以帮助你得到超低价钱的书，故选B。

　　3．If you turn to Olmenta, you ________.

　　A．need to pay more

　　B．need to add your own books

　　C．don't need to sign up

　　D．don't need to look for something specific

答案与解析：C　考查推理判断。根据最后一段第一句"If you're not interested in registering for accounts, adding your own books, or any of that hassle(麻烦)，Olmenta can suggest some solid titles to you based on general popularity and the citations of the people behind the site"可推知，在Olmenta网站，你可省去注册的麻烦，故选C。