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: Lausanne , Switzerland ( CNN ) Nuclear talks intensified Sunday between world powers and Iran , but key sticking points remained unresolved as the countries tried to reach a deal to curb Tehran 's nuclear program ahead of a Tuesday deadline . 2: The speed of which U.N . sanctions could be lifted remains in dispute . 3: Another sticking point : When would U.N. sanctions be lifted ?

1: sticking points 2: dispute 3: sticking point