For me it has to be this verse from Robert Frost’s poem “Stopping by the woods on a snowy evening”. It’s as follows:
The woods are lovely, dark and deep,
But I have promises to keep,
And miles to go before I sleep,
And miles to go before I sleep.
There is something about this verse that has stayed with me. It symbolizes that as humans we have so many duties to undertake and fulfil that we hardly get time to do the things we enjoy the most.