There are several synonyms for the phrase "be operative" that can be used interchangeably. Some of these synonyms include "be in effect," "be in operation," "be functioning," "be active," and "be running smoothly." Each of these phrases implies that something is working as intended and is producing the expected results. Other synonyms for "be operative" include "be capable," "be efficient," "be effective," and "be productive." These phrases can be used to describe a system or individual who is able to accomplish tasks successfully. Ultimately, whether you use "be operative" or one of its many synonyms, the message is the same; something is working correctly and fulfilling its intended purpose.