空穴来风未必无因

wind does not come from an empty cave without reason / there's no smoke without fire (idiom)

empty / air / sky / in vain

to empty / vacant / unoccupied / space / leisure / free time

electron hole (physics)

cave / cavity / hole / acupuncture point / Taiwan pr. [xue4]

to come / to arrive / to come round / ever since / next

lit. wind from an empty cave (idiom) / fig. unfounded (story) / baseless (claim)

wind / news / style / custom / manner / CL:陣|阵[zhen4],絲|丝[si1]

not yet / did not / have not / not / 8th earthly branch: 1-3 p.m., 6th solar month (7th July-6th August), year of the Sheep / ancient Chinese compass point: 210°

not necessarily / maybe not

certainly / must / will / necessarily

not to have / no / none / not / to lack / un- / -less

old variant of 因[yin1]

cause / reason / because