TKT Reflection: It is impossible in a class for a teacher to know why a students is making a mistake.

I don't agree with this thought. A teacher has been trained during all his/her proffesional training in different areas of education. If he/she has been properly trained, he/she should be able to identify and notice a student's mistake. Those can be grammar mistakes, pronunciation mistakes, to mention some. For instance, if a student makes a grammar mistake it must be the result of little effort on former teachers to correct or support that student.

Knowing our students help us to realize why they are making mistakes and where they come form. Those can also be the result of issues inside his/her family. Communication with the students is the best way to know why they have problems in learning.