My kid is 5 and she still has trouble constructing a full sentence. Like you, we have done therapies and all and like you until 31/2 my lil one had no words that she could get out of her. She understood everything and can carried out complex instructions, so she did understand. She is 5, and when it comes to words she will only say a few words, but her understanding has improved significantly. Recently she stared kindergarten where she is not doing all that bad. We know that it will only improve. Also, this seems to be common among homes that speak multiple languages, I mean think about it they are introduced to Nepali, English, Hindi, Spanish, Newari etc. and that is a lot for the child. The amazing thing is that they understand it all but just have not mastered a language to respond in, at least that is my take way.

I would suggest to not worry too much because this can get overwhelming and sometimes when it feels like the "sky is falling", the sky actually still stays where it always was. Be patient and love him or her to your fullest because they are unique to you, and they have unique needs, and unique ways to grow, and unique ways to learn. Some of us compare them to other kids and this does not do justice to them, and that is somewhat pointless in my view. That just leads to you being frustrated.Compare them to themselves, as to what they have done better than what has been done until now, and what could be improved. I wish you all the luck my friend. I know things will improve and trust me they will. Happy Dashain to you, your family and your special little one.