They have a little nest egg tucked away somewhere for a rainy day.

他们有一点藏在某处的应急积蓄。

《柯林斯英汉双解大词典》

Building a nest takes a day or two, and the female might create about 10 nests in total, often right next to each other.

修筑这样的一个巢室需要一到两天，并且这些工蜂们可能会修大约10间巢室——往往是一间挨着一间。

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Until one day, the mother stopped coming to the nest.

直到有一天，母亲再也不来巢窝了。

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Despite a smoggy start to the day, visibility at the Bird's Nest improved in the hours before the event began.

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Making small but regular payments into appreciating assets can form the basis of a rainy day fund or even grow into a sizable nest egg over time.

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Beijing's Bird's Nest, the wonder of the world in 2008, is underused, goggled at by day-trippers and the odd concert-goer.

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