operation of intracranial tumor

例句：

1. 1. The surgeon performed the operation successfully.
   外科医生成功地进行了手术。
2. 2. The patient underwent anoperation to repair his heart valves.
   病人接受了一次手术来修复他的心脏瓣膜。
3. 3. The operation was a success, butthe patient still had to stay in thehospital for several days.
   手术成功了，但病人仍然需要在医院住几天。