As they were settling down to sleep that night in front of an abandoned farmhouse, they heard the faint croaking of a kind of frog they couldn't identify.
是夜大夥兒露營於一間廢棄的農舍前，臨睡時忽聞蛙聲不絕如縷。仔細聆聽，這群對青蛙頗內行的生物系學生，卻都聽不出這是那一種蛙叫聲。