Saving air

Why, yes, join me in saving air

Don't breathe for 24 hours, that is

And save the air of a whole day

I did it once - 

But didn't feel well afterwards - Eh?!

I reckon it was that day

I wanted to find out what Carpe Diem meant

And by the time I found out, it was night

And no day left to seize. Doh!

And - you got out of that building yet?

You must follow the notice - 

This door must be kept closed at all times

You're tricking us, says Fido

Telling porkies

How come you didn't breathe for 24 hours?

Well, I must have been dead for a day

No change there then for me? Heehee.