To illustrate and teach young learners vocabulary for you could use objects to illistrate the words. For example, with animals, clothing, or fruit ,you could use actual objects such as clothing, toy animals, and plastic fruit. For young learners, it's a very useful tool in making the abstract concrete through visualization. Realia is also helpful in teaching prepositions of place. Objects can be placed on a desk, in a desk, under a desk etc. I hope this helps :)