It's very essential to start talking to your kids like a mini adult. Those gibberish voices may sound funny but it does much bad than good. Talk to them properly and explain them all little things around them. Trust me they hear and learn everything.
Ask them questions, simple ones too like where is you shoe, sock, sipper etc or how was your day, what all you did? And answer the question too, look it is here. This is your shoe, a tree and you know what we had fun at the swing.
Explain your actions- Look we are going to the park, we are removing shoes, cutting vegetables etc. This will help them learn new words and how to use words and make sentences.
Trust me, they will understand and respond in their own style.
Give small instructions to your kids- one easy instruction at a time. They won't be able to comprehend complex instructions so start with simple one or two words and keep increasing it.
Eg - come here, go there, sit on the chair, bring that and keep making it complex- keep that toy and come here.
Initially they may look blank or not understand. So, help them do the instruction and keep explaining them your actions.
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