I would like to believe this opinion, because I am able to speak both English and Chinese. 因為我會說英語和中國話，我願意相信這意見。But the best considered opinion, according to a well reported article in The Atlantic earlier this year,[1] is that there is no strong evidence that bilingualism is especially helpful for cognitive function in old age. No problem. 沒問題。

[1] http://www.theatlantic.com/science/archive/2016/02/the-battl...