这种合金中含有少量的镍以提高强度。

This alloy contains a small amount of ___nickel to enhance its strength.

我需要一个五美分的硬币来凑够零钱。

I need a ___nickel to make exact change.

我翻遍口袋也找不出一个硬币。

I searched my pockets but couldn't find a ___nickel.