Even with silk and hemp, do not throw away the rush and sedge.
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history
No standalone use in modern Chinese except as a rare surname. As a common noun it survives only in old texts naming the 蒯 rush used for mats and sandals. The phonetic inside is 蒯's right element, related to the kuǎi / guāi sound seen in 拐.
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Classical and onomastic only; you meet it in the 《诗经》 and in old personal names, not in speech.