advise :
please request trial class before register the course so that you can check is the teacher good or not.

when i studied at erican, I complaint that my teacher dont know how to teach(she only sharing the previous working experience and mentioned that she dont want to teach as want to speak to us more. main point she speak all the time. she say we can study the english book at home so better speak english more in class).
I informed to erican that if dont change teacher then whole class student dont join the course anymore.
1 month later, erican changed a experience teacher to teach. I learned and improved alot after new teacher came...

this is why we need to make a complaint sometimes