夜以继日
yè yǐ jì rì · HSK 7
night and day
🌙☀️ 夜 night + 以 by-means-of + 继 continue + 日 day = use night to carry on into day
夜 — 亠 lid + 亻 person + 夕 evening moon
夜 originally depicted a person (亻) under a roof (亠) with the moon (夕) beside them, evoking nighttime rest. The moon component 夕 carries the meaning of evening, while the surrounding elements set the scene of a person at night. Over time it came to mean 'night' in general.
以 — phonetic 㠯 (plow/tool) + 人 (person)
Originally a pictograph of a hand-held plow or tool (㠯), later combined with 人 (person) to suggest 'using' something. The core meaning 'to use' extended metaphorically to 'by means of', 'with', and 'because of'. In modern Chinese it functions mainly as a grammatical particle.
继 — silk radical 糹 + 㡭 (continuous threads)
继 means 'to continue' or 'succeed (to)'. The silk radical 糹 evokes threads being joined, while the right side 㡭 originally depicted unbroken strands of silk. Together they suggest splicing threads — extending what came before, hence inheriting or carrying on.
日 — pictograph of the sun
日 is a pictograph of the sun, originally drawn as a circle with a dot or stroke inside representing the sun's substance. Over time the round shape was squared off into the modern rectangular form. It means 'sun' and by extension 'day'.