Lucas Says:

aGain - yay !! it's clear now
down - when he falls
ites - when he wants the lights to be turned on to
play - (on Taiyi's organ)
bus - when he wants Taiyi to play "The Wheels on the Bus" on the organ
mo - when he wants to hear Elmo's Song on the organ
uh oh - when he drops something
no no - when he knows he's not supposed to do something or when he doesn't want something done to him (like wipe his leaky nose)

more things to come ! He's growing up so quickly I can hardly keep up with him !