The phrase "be seen" is a commonly used expression that refers to the act of being observed or noticed by someone. However, there are many other synonyms that may be used as a substitute for this phrase, depending on the context of the sentence. These synonyms include terms such as "be noticed," "be viewed," "be perceived," "be observed," "be watched," and "be witnessed." Using synonyms can help to add variety and depth to the language used in writing or speaking, making the message more interesting and engaging for the audience.