Question pretext
If ("dwellingType" == 1 OR "gqType" == 3,4,5,6) AND "age" >= 15 AND "usual_reside" == 1, then ask;
If "main_act" == "1 to 9", then ask;
Literal question
What is "person's" main Industry?
e.g. Selling toddy, small shop, motorbike hire, PWD