Whenever P.P. has only Q. The above two statements are statements in which P contains Q. These two statements are easily confused.
"If P, then Q" is called the implication expression of P and Q, marked as p→q, which means that P is the antecedent of the implication expression, and Q is the truth of the antecedent of the implication expression: only when the antecedent is true and the antecedent is false, the result is false, and the rest are true, which is a common expression.