In my understanding, the backbone teachers in your school go out for training, which belongs to the first-level training, and then they sum up what they have learned in combination with the actual situation of the school, form their own courses and teach them to other colleagues. This is the so-called secondary training. This method has several advantages: first, it saves costs; Second, the content of studying abroad will be processed after coming back, so the content is more in line with the actual situation of the school.