On my prior years' Form 1040s, I have not used the foreign tax I paid on stock dividends from popular foreign companies. The companies' ticker symbols are BCE, POT, AGU and HNP. Can someone give me a summary of how to proceed to apply these past years' foreign taxes to the foreign tax credit line of my 2017 Form 1040? I am reading the instructions for Form 1116 and having difficulty understanding them.