/hɑːrd ən ˈfɑːst ruːl/ – Phrase
Definition: quy tắc cứng rắn bắt buộc phải chấp hành.
A more thorough explanation: A “hard and fast rule” refers to a strict and inflexible rule or guideline that must be followed without exception. It is a fixed and unyielding standard that does not allow for any flexibility or discretion in its application.
Example: In this case, a hard and fast rule is that all employees must clock in and out for their shifts using the company’s timekeeping system.