Drangflies and Mosquitos

蜻蜓和蚊子原本是兄弟，体积一样。兄弟俩都靠吸人血生存。一日，蜻蜓目睹蚊子在吸血时被人打死。蜻蜓为自身安全，改为吃蚊子吸二手人血的方式谋生。而蚊子们一意孤行依然吃一手人血。结果截然不同：人类把蚊子定性为害虫，将蜻蜓尊崇为益虫。受保护的结果是蜻蜓的体积越来越健壮。
It was interesting that once dragonflies and mosquitos were brothers sharing the same size and shape, same food---human blood. One day, on seeing mosquitos stroke to death while dipping human blood, dragonflies, under the consideration of security, turned to eat mosquitos for their second hand human blood, yet mosquitos persisted to dip blood by their own. Since then, human being took mosquitos as pests, considers dragonflies beneficial, and eventually makes dragonflies greater in size.