There are questions from English, General Knowledge, Fundamental Mathematics and Reasoning. Apart from these, if you apply for Engineering position, questions will be asked from the relevant subjects also. Apply without fail to positions notified by the RRB of various places and do not confine yourself by applying to RRB, Chennai alone.
There are good opportunities for those who pass the examination and those who know Hindi. However, the examinations should be written in the respective places where RRB is situated.