This is a wug

I think Amy's just about ready for the Wug Test now -- she seems to be able to pluralise English nouns by adding -s, even without prompting.

(For the full Monty, she should be able to pick the right form /-z/ /-s/ /-Iz/; I don't think she's quite there yet, though IIRC the /-Iz/ form is usually the last to be acquired -- I think she tends to use /-s/ for all.)