I had undergone an operation in which part of a bone in one leg was used to replace the shattered bone in the other.

我经历过一场手术，用一条腿部分的骨头代替另一条腿粉碎的骨头。

youdao

youdao

The officer refused to let his men take part in the operation.

这军官拒绝让他的士兵参加这项军事行动。

《牛津词典》

Then the little ones go under the blow dryer. "They are so happy once they're de-oiled and it actually makes you feel pretty good that this part of the operation is being done to save these animals."

VOA: standard.2010.06.08

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