Question, exam, civil servant, I want to ask, how about the public exam of nitrogen introduction?

When I was preparing for the civil service exam, I asked my friends who came ashore about this. Everyone says that the public examination education of nitrogen guide is ok. They said that the teacher was very professional and taught a wide range of knowledge. After class, students who can't keep up with the progress will get a small stove. Later, I resolutely signed up for an introductory nitrogen class, and after three months of cramming, I went ashore.