There are many different voices in language, but applicative voice is a type of voice that we use when we want to show that someone is doing something for someone else or giving something to someone else.
Think of it like this: Imagine you have a cookie and you want to give it to your friend. You could say "I give my friend the cookie." This is an example of applicative voice because you are doing something (giving) that affects someone else (your friend).
Another way to think about applicative voice is to use a sentence like "I wash the car." This sentence doesn't have applicative voice because you are just doing an action without any interaction with another person. But, if you change the sentence to "I wash the car for my dad," now it has applicative voice because you are doing something for someone else.
In summary, applicative voice is a type of language that we use to show that someone is doing something for someone else or giving something to someone else. It's like doing an action that affects someone else, and it's important because it helps us understand who is doing what for whom.