Amy said just now, "Ich möchte lieber bei Auto in den Kindergarten!"; I wonder whether that's a loan-translation of "by car", though I'm not sure whether I've used that construction to her.
She also says, "Please help me by [activity]", which is a loan-translation in the other direction (cf. yesterday's "beim Ausschneiden helfen"), where I'd use "help me with [activity]".
And, in non-preposition news, Amy told Stella the other day what she'd like to eat: "Diese Zeit möchte ich ..." (as in "This time, I want to ...") :D
 As anyone who has learned another language can surely confirm, prepositions are indeed hard, cross-linguistically, because just about every language uses them a bit differently even in cases (such as closely-related languages) where it seems that a 1:1 mapping is possible. And then there are lots of 1:n (e.g. French "de" vs. Italian "di; da"? English "for" vs. Spanish "para; por"? these may be m:n, though...) and m:n mappings...