knock the bottom out of somethinginformalCHEAPREDUCE to make something such as a market or industry fail suddenly 使〔市场或行业等〕骤然疲软[不景气] A sudden drop in supplies of certain chemicals could knock the bottom out of the engineering industry. 某些化学品供应的突然减少会造成工程行业一时间的不景气。
knock the bottom out of something• A recession would knock the bottom out of corporate profits.
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