Translation:We have to read many books in this class.
I think Duo has been feeling the heat regarding marking typos wrong, so the engine now allows a single typo in Spanish. However, in some cases, like this one, the word with the typo is a recognized word, but a wrong one nevertheless. It's going to make learning Spanish more difficult.
In one of previous duo's task there was the note of old woman, English spoken, that she remember from her school studying time, that the right phrase should be: "We have to read a lot of books to this class". I've understood it as: we have to read a lot of books on vacations to be ready for the next school year. This point of view is more realistic, becuse now there is no such roole to read books in classroom. Duo developers: please didcuss this note and, if possible, add 'to this class' as valid answer. Thanks, Regards, AO.