You will be given a definition of a task first, then some input of the task.
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.

Sentence 1:The plan would allow passengers to go directly from the bus or tram platforms through an underground pedestrian walkway and escalators . Sentence 2:However , the construction cost of 3 million rubles ( 1988 value ) prevented the plan from being implemented .
Output:
however