What are the keywords in the following sentence? A bunch of people waiting by an air plane
bunch, plane, wait

What are the keywords in the following sentence? a map of the perimeter was released .
map, perimeter, release

What are the keywords in the following sentence? a triumphal arch erected by governmental body to commemorate person is victory over monarch .
arch, commemorate, monarch, victory

What are the keywords in the following sentence? Soldier is watching the train.
soldier, train, watch