2. A time of great tribulation that was to come in their lifetime (see verse 34).
4. Jesus was describing the great tribulation which was to come upon the nation of Israel during the siege and destruction of Jerusalem by the Roman armies.
6. Jesus told His disciples that when they saw Jerusalem being surrounded by the [Roman] armies they should know the destruction is near.
When they saw this start to happen [the first attack by Cestius Gallus in AD 66] (see Learning Activity #32), they should flee to the mountains (they went to Pella, see Learning activities #44 and #45).
A time was coming when judgment was going to come on the Temple, the city of Jerusalem and the people who remained in the city.
Many would be killed and taken captive.