Here follows a short story which finishes with a moral:

'When I finished the prep class I was sure I knew the English language perfectly. However, four years later I thought: "Well, maybe there are some things I still don't know."
'Then I went to the university and I started using the language on regular basis, while some of my classmates majored in English.
'On our graduation we met and we agreed that we'll never "know" or completely learn the English language.
'Finally, in the good English literature tradition, here follows the moral:
"Don't be deceit by how easy learning anything may look at a first glance - it will always prove much harder when you advance and you will never be able to fully comprehend or master it."
'And that, my friend, is an age-old truth.'