The phrase "be concerned" is a common expression used to indicate worry or unease about something. However, there are several synonyms for this phrase that can be used to convey the same meaning, albeit with slightly different connotations. For instance, the phrase "be troubled" implies a deeper sense of distress or upset, while "be anxious" suggests a state of nervousness or apprehension. "Be alarmed" connotes a heightened sense of urgency or fear, while "be bothered" indicates a more general sense of inconvenience or irritation. Ultimately, the choice of synonym will depend on the context of the sentence and the level of concern being expressed.