The ability of the Kangaroo

The zoo built a special eight-foot-high enclosure for its newly acquired kangaroo, but the next morning the animal was found hopping¹ around outside. The height of the fence was increased to 15 feet, but the kangaroo got out again. Exasperated², the zoo director had the height increased to 30 feet, but the kangaroo still escaped. A giraffe asked the kangaroo, "How high do you think they'll build the fence?"

"I don't know, " said the kangaroo. "Maybe a thousand feet if they keep leaving the gate unlocked.

袋鼠的能力

动物园为刚引进的袋鼠建了一个特殊的八英尺高的围墙。但是第二天早上，人们发现这动物在围墙外面蹦跳着。于是围墙高度增加到十五英尺，但袋鼠还是跑了出来。动物园经理甚感恼火，又叫人把围墙高度加到三十英尺，但袋鼠还是逃了出来。一个长颈鹿问袋鼠：“你认为他们会把围墙建到多高？”

“我不知道，”袋鼠说，“如果他们继续开着大门，可能要修到一千英尺吧。”