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: The win comes after a long history of military rule , coups and botched attempts at democracy in Africa 's most populous nation . 2: He will take the helm at a critical time , as Nigeria grapples with Boko Haram , serious economic woes and corruption . 3: Nigeria is the most populous country in Africa and is grappling with violent Boko Haram extremists .

1: Africa 's most populous nation 2: Nigeria 3: the most populous country in Africa