The phrase "acts part" is often used to describe someone who is playing a specific role in a situation or scenario. Some synonyms for this phrase include fulfilling duties, assuming responsibilities, executing tasks, taking on a role, and performing a function. Other similar phrases may include playing a part, assuming a position, working a role, or carrying out responsibilities. No matter what synonym is used, the idea is that someone is taking on a particular job or responsibility within a larger context or setting. This phrase can be applied to both individuals and groups, and is often used in professional and personal contexts alike.