Definition: You will be given three sentences. Read them, then identify a noun phrase (person, place, or thing) or event that is shared between all three sentences. As the output, write the span of the text corresponding to that phrase in each sentence. Keep the order of the sentences, that is, your answer should look like: 1: *a phras from sentence 1e* 2: *a phras from sentence 2* 3: *a phrase from sentence 3*
Input: 1: Yashasvi Yadav , Senior Superintendent of police in Lucknow , northern India , told CNN the city 's force has bought four drones and is in the process of purchasing one more . 2: Some say this method of crowd control needs regulation too . 3: Police in Lucknow , northern India , have bought four drones to help control crowds .

1: bought four drones 2: this method of crowd control 3: bought four drones to help control crowds