Republishing single sentences has previously been found to be a copyright violation, and copyright has been granted on as few as three notes. On the other hand (to pick a recent example), 50 Shades of Grey, originally written as a Twilight fan-fiction (derivative by definition) was never pursued for copyright violation (AFAIK).
It isn't clear to me whether that only covers works in a foreign language that claim to be translations of some other work, or whether it would apply to any foreign-language work that duplicates the plot of an earlier copyrighted work.
If I describe at an abstracted level the working of a C++ program to you and you implement it in Java then you have not copied the work, nor even created a derivative, ergo clean-room implementation being a thing.