It has three roots.

这种情绪有三个根源。

youdao

Roots of Peace says a landmine costs anywhere from three to thirty dollars to produce and place in the ground.

VOA: special.2010.05.03

Many growers like to start with two to three year old roots instead.

VOA: special.2009.04.07

And I set down roots three blocks from where I grew up.

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If the roots extend past three feet, chances are good that they can support the tree.

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She sold three million copies of her book and led a grass roots movement over 25 years, that required her to be on the road continuously.

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