The hem allowance is the width between the hemline and the hem edge.

底摆边高就是底边到折边的宽度。

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While I was at it, I overcast the top edge so I don't need to fold under a hem for the casing.

虽然我在这时候，我阴顶部边缘，所以我不需要折为下套管下摆。

youdao

They line roads and streams and hem in the woods and surround towns, and they crowd into back yards and edge up to gas stations.

路边、溪边、都种了玉米，林子、城镇四周也都种了玉米，玉米种满后园，甚至挤到了加油站。

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