When I ask Jonathan to pronounce words, sometimes he does it and sometimes he doesn't.
But I do notice that the best time to get him to speak words is before he sleeps. I don't know why but he does it pretty well.
Just a few days ago, while changing him before his bedtime, I had a short conversation with him about trying to pronounce words cos I was teaching him how to say "hello".
Me: Kai Ming, you must listen to the words and try to say it. You know?
Jon: "ah d no"
He confirmed to me that it was "I don't know"
Could have been a spur of the moment but me happy :)