Actually, I understood. I used to listen to Desert Island Disks 15 or 20 years ago--a local NPR affiliate's version.
One programming language? As I recall DI Disks let one pick 10 pieces of music, and threw in the Bible, all of Shakespeare, and a luxury of your choosing. But I suppose that if one were not distracted by King James, King Lear, or a luxury, the sensible thing would be to follow in steps of Wall, Ousterhout, Van Rossum, and Matz: use C and create an extensible scripting language.
So if you had to choose one programming language to do all of your work in, which language would it be?