现在分词的被动形式

* I saw her being taken to the operating room. 我看见她被送到手术室。
* The building being repaired is our library. 正在维修的那座楼是我们的图书馆。
* Not being invited to speak, you should remain silent at the conference. 没有被邀请发言，你就应该在会议上保持沉默。