Though he still sometimes sounds like a Dadaist poet, Conrad has mostly moved from babble and single-word utterances to two-word sentences that make sense in context, with occasional forays as long as seven words. He's collected enough nouns that I no longer keep track of how many words he knows.
The weird thing is how many sentences he can make with his tiny repertoire of only five verbs:
Want Go Get Have Bite
And that list tells you a lot of what there is to know about 18-month-olds