annotate an axiom in OWL

Dear All,

Given an axiom in OWL functional syntax "SubClassOf(Human, Animal)", how 
can I add annotation for it?

For example, I want to add the following annotations:
1) add comment "Humans are animal"
2) add "John created this axiom"
3) add "This axiom was created on Feb. 6, 2008"

Can anybody show me how to do this in OWL functional syntax?

Thanks,

Chuming