reinvent the wheelinformalWASTE something to waste time trying to find a way to do something when someone else has already discovered the best way to do it 无谓地重复,徒劳,白费功夫〔因别人早已发现做某事的最好方法〕reinvent the wheel• He had set out to reinvent the wheel; actually he wound up inventing it.• Without mentors we have to reinvent the wheel each new generation.• Learning by discovery doesn't mean reinventing the wheel each time you need to move the wagon.• I mean, why reinvent the wheel if it rolls?
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