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クソ暑い日に偉い人が来るってんで「偉い人が来るから…
→ “On this freaking hot day, a big shot is coming! So they say, 'Because a big shot's coming...'”
クソ kuso = fucking / damn (intensifier)
暑い atsui = hot (adjective)
暑 atsu = heat
い i = endings for i-adjectives
日 hi = day / sun (noun)
に ni = on / at (particle indicating time/location)
偉い erai = great / important / big-shot (adjective)
偉 eri = great / noble
い i = endings for i-adjectives
人 hito = person (noun)
が ga = is / subject marker particle
来る kuru = to come (verb)
来 ki = come
る ru = infinitive verb ending
って tte = saying that / quote marker (colloquial contraction of 'to' + 'te')
と to = quote marker
て te = connective form
んで nde = because / so (colloquial contraction of 'node')
の no = explanatory particle
で de = causal connector
「 " = opening quotation mark
偉い erai = great / important / big-shot (adjective)
偉 eri = great / noble
い i = endings for i-adjectives
人 hito = person (noun)
が ga = is / subject marker particle
来る kuru = to come (verb)
来 ki = come
る ru = infinitive verb ending
から kara = because / since (conjunction)
…」 ..." = ellipsis / trailing off (closing quotation mark)