다음 중 틀린 문장을 찾아 바르게 고쳐라(a)history proves that conversation can be a very powerful tool, giving us not only hope but also the courage to act. (b)the solidarity trade union movement in poland, for example, began as a mere conversation about freedom and change among a handful of workers in a gdansk shipyard. (c)within months, the movement grew to 9 million members. (d)the movement could no longer ignore, and political change soon followed.

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