2111-3111 is a kind of work as a waiter, clerk and cashier, which is relatively easy, but the salary is not high.

4111-5111 is a kind of ordinary worker, which is very hard and depends on overtime.

from 1,111 to 21,111, it's food delivery, express delivery and general sales, and it's really hard. In addition, some middle-level supervisors, engineers and the like are also this number.