He underwent a three-hour heart operation.

他接受了三个小时的心脏手术。

I underwent an operation on my groin once.

我的腹股沟部位曾动过一次手术。

My mother underwent major surgery last year.

我母亲去年动过大手术。

Only 12 weeks ago he underwent major heart transplant surgery.

仅仅12周之前，他接受了一次心脏移植的大手术。

When she first underwent IVF it was still a relatively new procedure.

她第一次接受体外受精时，那还是一个比较新的方法。