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    "You'll think twice about plucking your eyebrows (拔眉毛) you find their important role," says Greg Foot. They are one of most expressive(有表现力的) parts of our bodies. your eyebrows, you can tell your feelings to other people. is that their only purpose (目的)?

    Over several thousand (year), we have lost lots of body hair, so it's strange that hair still (remain) on our brows. Some scientists say that eyebrows mainly work as special form of protection for the eyes. In fact, their job is so (importance) that some researchers are sure that if we didn't have (they), we'd have evolved (进化) some other facial features to (do) the same task.