Sorry if this is a really open-ended question, but one thing occurred to me when I was asking a prior question here; are there any particular grammatical errors frequently made by native Japanese speakers?
For example, in English there are quite a few obvious mistakes that native speakers make -
me and Sally went... rather than
Sally and I went... and often non-native speakers of English are better at distinguishing between them than native speakers.
Is there any such Japanese grammar that is commonly used incorrectly by native speakers?
I am more interested in common mistakes than obscure mistakes; mistakes where one would think that a native speaker should know better.