answer: #Person1# asks #Person2# what they need to do when they check in at the Air China's counter.
documents: #Person1#: We're supposed to check in at the Air China's counter 30 minutes before take-off, Joe.
  #Person2#: Yes, I know. The boarding time on the ticket says 17:05, and now it's 16:15. I guess we have plenty of time.
  #Person1#: Do we need to show our ID cards when checking in?
  #Person2#: Yes. It's essential.
  #Person1#: What about our luggage?
  #Person2#: We can check it and hand carry the small bags. And we have to open each for inspection.
  #Person1#: Are they going to frisk all the passengers?
  #Person2#: I think so. We certainly don't want a hijack to happen on the plane today.