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时间过去三年了,但我制作的“蜻蜓演变标本”至今保存完好,无论春夏秋冬,可随时拿出来让幼儿观察。通过观察实物标本,幼儿能一目了然地看出蜻蜒生长演变过程,说出靖蜒的特征及蜻蜒与其幼虫的区别。这种实物标本,制作方法简便易行。制作过程:①找七、八个玻璃瓶,用清水洗净备用。备酒精200克。②5月底或6周上旬到池塘里找到蜻蜒卵和幼虫(俗称水蝎子)。③把蜻蜓卵浸在装有
Over the past three years, but I produced the “dragonfly evolved specimens” so far intact, regardless of seasons, can always be taken out for children to observe. By observing the physical specimens, young children can clearly see the evolution of the growth of the dragonfly, to say the characteristics of Jing-qing and the difference between the dragonfly and its larvae. This kind of physical specimen, making method is simple and easy. Production process: ① find seven or eight glass bottles, washed with water spare. Prepared 200 grams of alcohol. ② late May or early 6 weeks to find the pond dragonfly eggs and larvae (commonly known as water scorpions). ③ the dragonfly eggs immersed in equipped