DS2 (3.10) couldn't understand visually-presented choices or two-step sequences six months ago so I hope no-one will mind me being chuffed that this morning, after calling me with no effect, he came into my bedroom and said "why you stay in bed?". The other day he saw we'd tidied up his jigsaws and said "why you break my jigsaw?"
It took about six months to move from first "rehearsing" and "playing with "where?" questions ("where's DS1? DS1's at school!") to really "owning" the questions IYSWIM (ie he can now ask where something is because he wants to know, not because it's a game). And he's just started to be able to answer questions like "what are you wearing on your feet?"
DH and I have been religiously avoiding "why?" for so long that it will be quite hard to get it back in our vocabulary I think! I am hopeful that DS2 has made a more fundamental step of understanding the whole concept of a question (which he didn't understand at 3.4, just like he didn't understand the concept of choice, or what was happening next) which may speed things up.
Anyone else out there with receptive language problems who has got to "why?" or is getting there? How did you encourage it? I'm thinking I might try the "game" approach again with things I know he has grasped cognitively like "why do we need the umbrella? because it's raining!". Explaining "why" he needs haircuts or short sleeves with any effect still seems a long long way away!
It's my hope that he'll (1)really understand and use "why?" questions and (2) be able to tell adults when he hasn't understood something, before he starts school in a year's time. oh, and that he'll do more than parallel play by that time too. Still - took him for a walk with best friend yesterday and although he still can't converse, he was attempting to respond to lots of the comments that best friend made .