When you taught us before, you often helped us patiently. Answering problems for us, correcting our mistakes carefully, and greatly improving our English. We thank you very much.
When you taught us before, you used to help us patiently. Answer difficult questions for us, carefully correct our mistakes, so that our English has been greatly improved. We thank you very much.
When you taught us before, you always helped us patiently. To solve our problems, carefully correct our mistakes, so that our English has been greatly improved. We thank you very much.