Also the date the book was published will help. Anything written in the past few years is probably safe, though if there is a lot of slang, it may not be. Anything written before 1920 is probably not. As for the middle ground... Google is a good suggestion.
Hard call - there is no obvious way but to figure out the reality around you (for example, ask in this forum). That does not guarantee perfection, but only increases your chances of getting it right.