Your child's thinking is now getting sophisticated. He is better at telling the difference between fantasy and reality. He can maintain the topic of conversation and take turn speaking. He will maintain eye contact and will use language for multiple goals like gaining information, persuading others, etc. Questions will be fewer and more meaningful. He will use complete sentences with 5 to 6 words and his vocabulary and language skills are also developing quickly. He will be learning 5-10 new words a day. He will be quite chatty, will tell jokes, express ideas and describe situations and events.
What you can do
You can play spot the difference games, where he observes, thinks and verbalizes what he notices. He understands the different elements of story and can retell, extend or predict what happens in a story. He is now a concrete thinker and with language expanding, his conversations get to a more meaningful level.