My mother underwent major surgery last year.

我母亲去年动过大手术。

《牛津词典》

What they expected to be the removal of a small lump turned out to be major surgery.

他们本以为只是切除一个小肿块，结果却成了个大手术。

《柯林斯英汉双解大词典》

"Major surgery" can take many forms.

“主要手术”可以有很多形式。

youdao

He accepted the award in a wheelchair after a minor operation became major ankle surgery.

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"Well, you have all the risks that go with major surgery, " he answered calmly.

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Vanilla Blush was set up by 33-year-old Nicola Dames after she had major surgery in 2006.

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The reshaping procedures are major surgery, and they create thick scars that can be many inches long.

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