Sentence examples for Cause concern from inspiring English sources

No, "Cause concern" is not a complete sentence and is not grammatically correct
It is missing a subject and a verb. It could potentially be used as a phrase or clause within a larger sentence, but it would need to be accompanied by a subject and verb to make sense. For example: "The recent rise in crime rates has caused concern among local residents." In this sentence, "has caused concern" is a clause that completes the thought and is grammatically correct.