A chance meeting with an old man in leather on a foggy morning, told with a shrug and a grin. The repeated 'how do you do' makes a fine call and response.
From Mother Goose / Nursery Rhymes (traditional). See the whole collection.
One misty moisty morning,
When cloudy was the weather,
I chanced to meet an old man,
Clothed all in leather.
He began to compliment
And I began to grin.
How do you do? And how do you do?
And how do you do again?
About this rhyme
A chance meeting on a foggy morning, dressed up entirely in rhyme. The old man in leather is complimentary, the narrator grins, and then it's just how-do-you-dos, over and over, which is really the point: it's a rhyme built for practising greetings and getting the giggles from repetition. Say the last line slower and slower each time.
Public domain. Text from The Real Mother Goose (Blanche Fisher Wright, 1916), via Project Gutenberg. View the source edition