These patients had been operated on for the primary cancer but there was evidence of secondary tumours.

这些病人曾因原发性癌症做过手术，但是又有了继发性肿瘤迹象。

《柯林斯英汉双解大词典》

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Grandma was diagnosed with brain tumour, but luckily, the surgeon operated on her and removed it successfully.

奶奶被诊断出患有脑肿瘤，但幸运的是，医生给她做手术切除了肿瘤。

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Doctors operated on him later that year to try to improve the flow of blood from his heart.

VOA: special.2010.02.07

When you think about an int or a float or a dictionary or a list, you knew that there were functions that operated on them.

当你想到整型，浮点型，或者链表时,你知道可以用函数去处理他们,但是当你传递一个参数，例如链表。

麻省理工公开课 - 计算机科学及编程导论课程节选

Before that time, submarines had operated on diesel fuel and electricity.

VOA: special.2010.06.11

Jones has returned home and after being assessed will be operated on next week.

BBC: Prop Jones set for six months out

"She's holding her own, " said Michael Lemole, a neurosurgeon who operated on Ms Giffords.

BBC: Bill Clinton: Politics must change after Arizona attack

Last weekend an Italian surgical team operated on four-month old conjoined twin girls from Greece.

BBC: NEWS | UK | Magazine | Why are there so many conjoined twins in the news?