The top of the skull is flat with a slight vertical furrow and is approximately as wide as it is long.

头顶平坦，中间有轻微的纵向凹痕，脑袋的宽度与长度相等。

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Now Allergan, maker of Botox, wants to spread fear of "brow furrow"--age-related vertical lines between the eyebrows--to middle America.

FORBES: Smooth Operator