I found a student plagiarizing yesterday. My first thought was that she was writing better than my grad students, my second thought, that she was writing better than me in Spanish... My third thought, that I should google a few combinations of words to find her source. It was classic copy and paste, with whole paragraphs lifted from a very well-known journal in my field.
Now I'm beginning to prefer the classic Spanish student prose. It's awful, but at least it is distinctively theirs.