What are the keywords in the following sentence? class locomotive at station with a passenger train
class, locomotive, station, train

What are the keywords in the following sentence? football player argues with man after conceding a penalty during the period of the match
concede, match, penalty

What are the keywords in the following sentence? save water in your garden with these easy tips .
garden, save, tip, water

What are the keywords in the following sentence? politician arrives on stage during an event .
arrive, event, politician, stage