Reminds me of a rather odd thing that happened to me in the 1980s...

My then wife and I were about to depart on a visit my parents in southwest France and had decided that we should take the opportunity to explore the architecture of Barcelona, only 200Km down the autoroute. We didn't have a word of Spanish between us, nor the money to buy any of the acknowledged language courses. We were really thrilled when she came across what appeared to be a school textbook on learning Spanish in a secondhand bookshop in Newbury, Berks, for pennies.

Got the book home and discovered it was published in the US, no big deal, just maybe some nuance shifts. The book was split into sections such as "In the Market Place", "Public Transport", "On the Road" etc.

Useful phrases included:

From "In the Market Place":
Government forces are approaching, we should disassociate ouselves from the demonstrators.
These detonators are old and unstable.

From "Public Transport":
I think those passengers are from the resistance, we should get off at the next stop.

From "On the Road":
There are checkpoints now on all major highways.
The high mountain passes are not watched.
The border guards are not expensive.

I never really understood who wrote it, or for whom they wrote it, wasn't very useful in Catelonia though. "Fill her up" and "Where is the the toilet" were more the sort of things I had in mind.