True propositions and false propositions are learned in the second semester of the second grade, but those who have more mechanics should understand them in the first grade and will study further in the future.

In junior high school mathematics, true proposition is called true proposition and false proposition is called false proposition.

To judge whether a proposition is true or not, it is often necessary to proceed from the conditions of the proposition and draw a conclusion through reasoning, so as to judge the proposition as a proposition. This process is called proof. To judge whether a proposition is a false proposition, we only need to give an example (counterexample) that conforms to the proposition but is not satisfied, so we can judge it as a false proposition. We usually call this method "counterexample".