老师您好，我能理解【Foreign exchange gains arise because of the change in the exchange rate between the investor’s currency and the currency that the foreign shares are denominated in.】，但是我想不透下面这段原版书的例子。
题库有些关于ADR和汇率的问题，我常错，看了解析也一知半解，所以希望老师能说明下面三句话的言外之意到底是什么，谢谢老师！
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一：US investors who purchase the ADRs of a Japanese company will earn an additional return if the yen appreciates relative to the US dollar.
- 美国投资者买日本公司的ADR，这ADR以美元计价，日圆升值（即美元贬值），投资人为啥还能得到additional return？日圆变贵了，一美元可以买到的日圆变少了，怎么不是loss?
二：if the total return for a Japanese company was 10 percent in Japan and the yen depreciated by 10 percent against the US dollar, the total return of the ADR would be (approximately) 0 percent.
- 日本公司在日本的回报率是10%，日圆贬值+美元升值，我知道汇率的改变会影响美国ADR投资人的收益率，但ADR投资人的收益率怎么会被日圆贬值+美元升值的幅度给抵消？
三：If the yen had instead appreciated by 10 percent against the US dollar, the total return of the ADR would be (approximately) 20 percent.
- 日本公司在日本的回报率是10%，日圆升值+美元贬值，日圆变贵了，一美元可以买到的日圆变少了，怎么ADR投资人收益率不降反升?
