This can't be generalized. I suggest you listen to it first and see how it works. At present, the sales staff of training institutions are very powerful, and they are dizzy when they are fooled. If you think it's ok, you'd better not apply too much at once. It is best to apply for a subject or a small class first. You know, in today's society, you are an uncle before you pay the money, and you can try again after you pay the money ... and you may think very well, but it is doubtful whether you can persist in listening. Many people pay thousands of dollars and never go again after a few classes. Why bother? So it's better to be cautious.