您這問題提得太好了!應該是半邊U型裝彎曲。簡單說法就是轉彎處不能直來直去，要像U型管樣有一定的幅度拐彎。

来源: sillywoman 于 2019-08-15 19:57:37 [博客] [旧帖] [给我悄悄话] 本文已被阅读：次

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