过去是一种已经发生的未来。
The past is a kind of future that has already happened.
I do not know what I may appear to the world, but to myself I seem to have been only like a boy playing on the sea-shore, and diverting myself in now and then finding a smoother pebble or a prettier shell than ordinary, whilst the great ocean of truth lay all undiscovered before me.
The only way to learn a new programming language is by writing programs in it.