He needed to pee.

他要小便。

《柯林斯英汉双解大词典》

When one of our friends announces she has to pee, we all feel obligated to stand up and chaperone her to the bathroom.

当我们中的某一个说要去小便的时候，大家觉得应该马上站起来陪她去洗手间。

youdao

Poop and pee have lots of germs in them, so we need to wash our hands every time after we go potty.

大小便里有很多细菌，所以每次便后我们都要洗手。

youdao

He recommended we thump the taps, so while my husband and I went upstairs to try this, my three-year-old son ran for a pee into the marble-clad bathroom whose door opens directly onto the shower floor.

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