As a counterpoint, my sister learned German in college, going on to get a Master's and becoming fluent --- rather envy her that and often wonder what would have

As a counterpoint, my sister learned German in college, going on to get a Master's and becoming fluent --- rather envy her that and often wonder what would have happened if I had chosen (or been offered the choice of) a different language when making the selection when I enlisted. Similarly, the French Foreign Legion seems to be quite successful at teaching French.