Please note that we won't solve homework questions for you here. If you ask a specific question, or a general question about the topics you're studying, we can probably answer that.
In this case, I would assume you should include the whole sentence or phrase in your tree. When it says there are two trees, it is probably because there are two different ways to draw the whole tree, with two (ambiguous) readings.
I am assuming this is about
syntactic trees. When you say "word trees" maybe you are correct in splitting it into two different words (with "toy car" as one "word"). But that depends on your class/instructor/textbook. (This is one reason that asking homework questions here may not be very helpful-- there are different ways to answer similar questions depending on exactly how you are being taught!) Usually in a syntax tree words are not split apart (so "crasher" would be one node, not split into two), although in some advanced theories (
probably not what you'd be taught in an intro class) like Distributed Morphology syntax and morphology may be analyzed together within the trees.
(
https://en.wikipedia.org/wiki/Distributed_morphology )
