The first one I taught was mainly about phonetics and pronunciation and I didn't work with the textbook at all. It took me about 3 hours to prepare for it. For the second lesson, we agreed that the teacher would need to start discussing according to the textbook (until then, she had hardly used it either). She told me which exercises she would like to do and let me argue with it. I didn't know for a long time how to conceive the exercises so that they would be useful to the students at all.
For the second lesson, we agreed that the teacher would need to start discussing according to the textbook (until then, she had hardly used it either).