If you have ever read a children's book in your native language, you will probably see so-called nonsensical sentences, such as the mouse drives the car. If sentences like these help children learn their first language, then it makes sense for adults to learn their second language this way, as well.
The point of non-sensical sentences such as this and, "the lion writes letters"- "O leao escreve cartas" are to teach us to better understand the words, even if the sentences don't make a lot of sense. These exercises force you to understand each word of the non-sensical sentence, not just the gist of it.
New words are often but not always presented in unnatural contexts but usually introduced in sentences that make sense. The purpose of doing it both ways is to reinforce the word itself. The first presentation, where we choose the correct pattern from a jumble of words, teaches the new word in context. When it turns up in an unexpected place it tests our memory of the word. If we see or hear words only in their normal contexts, it takes longer to fix it in the mind as active rather than passive vocabulary.
You obviously don't have kids, a Wonder Woman cape? And mice eat nearly anything. I don't think there's anything wrong with the "nonsensical" sentences, it tests my knowledge and memory a lot better then having the same sentences repeated. As long as it's grammatically correct, I think it helps when trying to construct slightly strange sentences that you may want to use at some stage.
Indeed. My first thought was that mice got into someone's closet and chewed enormous holes in their cape. As for other sentences with animal actions that animals don't normally do, I think of Aesop, Babar, et al. ^_^
A little bit of anthropomorphism goes a long way. And now I have the urge to order a Portuguese translation of Redwall.
I suggest it's partly to mix words that have similar English equivalents with those that don't, like abacaxi, to give us more quickly a bigger wordstock to manipulate. Also note that the sentences often underline different meanings of the same word by using it in different contexts. This is a sound way to develop gradually a sense of the language, Sprachgefuehl. Mostly the program spoonfeeds, which is appropriate, but sometimes it seems to be trying to stretch that sense. Also, I'm finding that making mistakes with new or unprepared material helps me focus and remember. I think this is really a very sound program--just weak in clear pronunciation and coming up with idiomatic translations.