The idiom "半途而废" (bàn tú ér fèi) is formed through a classic four-character metaphorical structure common in Chinese, originating from the *Book of Rites (礼记)*. It is a compound phrase where "半途" (bàn tú) literally means "halfway on the road/path," and "而废" (ér fèi) means "to abandon/stop." Grammatically, "而" serves as a conjunction linking the adverbial phrase "半途" to the verb "废," creating the sequential meaning of "abandon upon reaching the midpoint." Thus, the term figuratively conveys the idea of giving up on a task or goal before its completion, deriving its meaning from the literal image of stopping a journey midway.