Multihour pauses in flights to the other side of the world are common, especially at HKG. Close to 60 per cent of all Canadians flying into Asia pass through here, many on layovers that average between four and 12 hours.
Where's a verb? I leanred there should be a verb in a sentence.
What's the grammar of the "that"?
I just guess the meaning is "Canadians on layovers pass the time between 4 to 12"