And a much more efficient product will be either a diversified mutual fund or an ETF product.

更有效的产品要么是多元化的共同基金， 要么是 ETF 产品。

So you think you're buying into a diversified fund with 500 different US shares, but actually two of them account for getting them for a fifth of the exposure.

因此，您认为您正在购买一支拥有 500 股不同美国股票的多元化基金，但实际上其中两股占了五分之一的风险敞口。