因为在该事件中，枪击凶手使用其母亲的枪，本人并没有受到背景调查。

There, the shooter did not have a background check; he used his mother's guns.

youdao

但是NTSB发言人凯斯·赫尔维说，委员会也将调查疲劳驾驶是否在该事件中起了作用。

But Keith Holloway, an NTSB spokesman, said the agency would also look into whether fatigue played a role in the incident.

youdao

在该事件中，参加者面在不吸气的情况下尽可能长时间的朝下漂浮在水上，该事件的世界纪录是11分35秒。

In this event, participants float face down on the water for as long as possible without coming up for air. The world record for the event is 11 minutes 35 seconds.

youdao