I am a teacher, and as a teacher I know that when I have tried to teach the same lesson for a hundred times and still the pupil does not understand, then I am forced to the conclusion that perhaps there's something wrong, Either with the lesson or with the teacher.
Irakaslea naiz, eta ziurtatzen ahal dizuet, lezio bera 100 aldiz azaldutakoan, ikasleak ez badu ulertzen, ondorioztatu beharra dagoela okerren bat dagoela, ikasgaian ez bada, irakaslearengan.