Instructions: In this task, you are given two sentences in the English language (Sentence 1 and Sentence 2). Your task is to identify the connecting word between the two sentences.
Input: Sentence 1:The first completed 417 m ( 1,368 ft ) tall World Trade Center tower became the world 's tallest building in 1972 . Sentence 2:However , it was overtaken by the Sears Tower ( now Willis Tower ) in Chicago within two years .
Output:
however