突如其来
tū rú qí lái · HSK 7
happening suddenly
⚡ 突(sudden) + 如(as if) + 其(it) + 来(comes): suddenly, as if it just came
如 — woman radical 女 + mouth 口
Originally a phono-semantic compound where 女 (woman) suggested compliance and 口 (mouth) indicated speaking or following orders. The early sense was 'to follow' or 'to comply with what is said,' which extended to 'to be like' or 'as if.' Modern uses like 'if' and 'such as' grew from this comparative meaning.
其 — top 八 + winnowing basket 其 (originally 箕)
Originally a pictograph of a bamboo winnowing basket, now written 箕 with the bamboo radical added on top. The original form 其 was borrowed phonetically to write the pronoun and particle meaning 'his/her/its' or 'that.' This loan use became dominant, so a new character 箕 was created for the basket meaning.
来 — pictograph of a wheat plant with grain heads
来 originally depicted a stalk of wheat with drooping grain heads, and meant 'wheat' in oracle bone script. It was later borrowed phonetically to write the unrelated verb 'to come,' which became its dominant meaning. The original 'wheat' sense was taken over by 麥 (now 麦).