Teachers’ comments | Types of mistake |
1. A good student of mine said, the clouds were sick and it was raining a lot but he quickly corrected himself and said ‘thick’ | Pronunciation slip |
2. I have several students in my top class who still say things like is very nice; he do; I am doctor. I just don’t know what to do about it. | Fossilised grammatical error |
3. At the beginning, all my students used terms like nice or good, for anything positive, then they gradually started to use language more precisely. | Lexical developmental error |
4. During his presentation this morning, my best student was so nervous that he said my mother, she is coming to visit me. | Grammatical slip |
5. Nearly all the students in that class who share the same language say brothers when they mean brothers and sisters. I don’t know why. | Lexical interference error |
Numbers 1, 4 and 5 are just slips or mistakes.
Number 1: it's unlikely that an advanced learner doesn't know that it should be he goes.
Number 4: it's also unlikely that an intermediate speaker doesn't know that won't is followed by the infinitive, not the -ing form.
Number 5: it's unlikely that an upper-intermediate student doesn't know that it should be it not that in this case.
Numbers 2 and 3, however, are real errors.
Number 2: the speaker clearly doesn't have the word steps in his or her vocabulary
Number 3: there are lots of errors: the form of the genitive (it should be the roof of the house), the form of a passive (it should be the verb be followed by the past participle, blown) and the tense of the verb (it should be was or has been). So many errors in one sentence need attention. It is possible that the teacher has chosen a task which is simply too difficult for the learner and that is a teacher-induced error.
Sources to practice:
https://www.eltconcourse.com/training/tkt/tktmodule1/practicetests/tkterrorpractice1.htm