Oh I could’ve, I would’ve, I should’ve,

　　Yes I should’ve

　　Done this or that.

　　But no, I didn’t,

　　I’m sorry, I didn’t.

　　I left it flat

　　But don’t despair,

　　I’m nearly there,

　　You virtuous chaps.

　　This year I’ll do it,

　　I’ll really do it.

　　Perhaps.

　　In spoken English, we often shorten auxiliary or “helper” verbs. For example, instead of saying “did not” we often say “didn’t”. When we write words that we have shortened, we write an apostrophe ( ’ ) to show that we have left some letters out. There are lots of examples of this in the poem.

　　Could’ve is short for could have.

　　And would’ve and should’ve are of course short for would have and should have.

　　Didn’t means did not.

　　Don’t means do not.

　　And I’m means I am, and I’ll means I will.

　　In the sixth line of the poem, “I left it flat” means “I left it (the thing she wanted to do) and did not do anything about it”. “I left it flat” is not really a normal English expression – but I think the writer needed to find something to rhyme with “that” in the third line!