In the ridibooks app itself I haven't found a way to copy/paste text directly. It's possible to highlight a sentence, click "search", and then in the search box you can tap the sentence, pick "select all", and then "copy", but it's cumbersome.
This lets you just highlight the sentences you want, and then get them from your account on ridibooks.com.
![](https://s2.save4k.ru/pic/XKU-9ndU9Ng/maxresdefault.jpg)