The two national key disciplines are mechanical engineering (code 0802) and civil engineering (08 14).
The four national key disciplines of the two disciplines are international trade (020206), analytical chemistry (070302), control theory and control engineering (0811) and environmental engineering (083002).
As far as I know, automobile, electric power, chemistry, civil engineering, insurance and construction are all good ~ ~
In fact, there is no difference between good and bad majors. The key lies in whether it suits you and your interest and love for that major ~ ~