What are the keywords in the following sentence? coal is being loaded on a historical steam train
coal, load, train

What are the keywords in the following sentence? rob paying careful attention on the muddy roads .
attention, pay, road

What are the keywords in the following sentence? footballer is sent off by referee during the match
footballer, match, referee

What are the keywords in the following sentence? sunrise over the birch forest in early spring with fog and blurred by haze
fog, forest, sunrise