the usual, ordinary

to keep up; to retain / to maintain

always, invariably, all the time / usually / (with a negative verb) never

role

accomplish, perform, fulfill

(software engineering) class diagram - A type of static structure diagram that describes the structure of a system by showing the system's classes, their attributes, and the relationships between the classes.

harmony

(education) class (group of students in a regularly scheduled meeting with a teacher) / class of things (typically products) sharing certain features / (programming, object-oriented programming) class

(aviation) economy class

business class