Okay kiddo, have you ever noticed that some words in different languages look and sound almost the same? These are called cognates. For example, 'cat' in English is 'chat' in French.
Now, let's talk about a special kind of sentence that uses cognates. This sentence has two parts: a subject (who or what the sentence is about) and a verb (an action word). But instead of having an object (who or what the verb is happening to), the verb is doing the action to a word that is almost the same in another language.
Let's put these pieces together with an example: "I like to eat pizza." But instead of "pizza," we use the French word "pizza" (because it sounds like the English word): "I like to eat pizza." This French word "pizza" is the cognate object.
So basically, a cognate object is when we use a word in a foreign language that is very similar to the word in our own language, instead of using a typical object.