question, problem on homework etc. / a question; a matter (of time etc.) / a problem (something that needs to be dealt with); a trouble / an issue; a matter

looks back, double-takes (often as 一(いっ)顧(こ) (ikko)) / (figuratively, chiefly in the negative) care, concern; amount one cares

look back, turn back, turn around / remember, review, examine

天文台: observatory

檸檬色: lemon (colour)

(chiefly Kansai) Synonym of きだい (kidai, “Dentex tumifrons”)

unthinkable, out of the question

practical question (problem)

observatory (place where celestial bodies are observed)

set of problems