Yes Idioms are mostly four-character, but also three-character, five-character or even more than seven-character; Many idioms are handed down from past dynasties, such as important historical events, myths and fables in ancient books, classic quotations and so on. And closing the door to beat the dog means closing the door to beat the dog so that it can't escape. Metaphor surrounds, defeats or annihilates the enemy, which belongs to the idiom category. For example, in Revelation of History, the conquest of Jinzhou in World War I resulted in a favorable situation of closing the door and beating dogs, and then the enemies of western Liaoning and Shenyang were wiped out.