Something about the knowledge of mechanics and electricity since these two factors is the most important thing of a train in Hong Kong. Explain some working experience of your last job and let them know you are suited for this job.
I applied through university. I interviewed at MTR (Hong Kong) in Oct 2025
Interview
There are many managers and department head in the teams chat room, and most of them will ask you a few questions of your knowledge or the project you worked.