In the sentence ".while power dams were left behind with a 14.7 percent share." ...

Questão de Inglês da banca CESGRANRIO aplicada no concurso Petrobras (2008). Confira a resolução completa abaixo:

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In the sentence ".while power dams were left behind with a 14.7 percent share." (lines 10-11), the word "while "