He used to have short hair, but now he wants to grow it long.

他过去是短头发。现在他想把头发留长了。

youdao

It was so cold that the men let their facial hair grow very long.

VOA: special.2009.01.24

Outfielder Kirk Nieuwenhuis let his hair grow long again after buzzing it all off last summer.

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If you are going to grow it, it is a rather long-season plant, clocking in at about 112 days from seeding.

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Its projection for GDP growth was that it should continue to grow at its long-run historical average.

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