短语讲解：

1. The incident took place while Iran and the U.S. are negotiating Iran’s nuclear program and international economic restrictions.

take place 发生，举行
例句：Earthquakes take place far underground.
地震则发生在地球的极深处。

2. At the same time, the U.S. is supporting Saudi Arabia in its air campaign against Iranian-backed rebels in Yemen.

at the same time 同时; 一起;但是; 然而
例句：The machines all started up at the same time.
所有的机器都同时开动了。