Language milestones refer to your child's ability to use and understand language so that they can effectively communicate. While every child develops at a different rate, typically by the age of 6 and 7 your child will have a vocabulary of several thousand words.
They're now able to have more logical thinking, more abstract thinking and they'll have more complex problem solving abilities. They know the days, the seasons, the months, the year and they will be able to speak to you in complete sentences using pretty much correct grammar most of the time.
This is a great opportunity for your child to continue to learn and grow through using their language and communication skills. They're really much more reflective and they're really understanding things a lot more. So for example, if dad went outside, if he left the house and you say 'Oh, dad went to take a drive to the grocery store but the keys were left on the counter' he will say 'He couldn't have done that because his keys are here' and they're able to make that understanding and they'll probably be able to make even further complex problem solving skills.
So encourage more opportunities to ask them about their day and for them to tell you the things that they're doing and to be descriptive and ask follow up questions.