Since I’m so late, here’s one from the Poems Written in Early Youth section of The Complete Poems & Plays of T.S. Eliot. You can find this section hiding at the very end of the book. And you will find it because just about everybody knows somebody with this edition.

Song

If space and time, as sages say
   Are things that cannot be,
The fly that lives a single day
   Has lived as long as we.
But let us live while yet we may,
   While love and life are free,
For time is time, and runs away,
   Though sages disagree.

The flowers I sent thee when the dew
   Was trembling on the vine
Were withered ere the wild bee flew
   To suck the eglantine.
But let us haste to pluck anew
   Nor mourn to see them pine,
And though the flowers of life be few
   Yet let them be divine.