This is the problem of cars and goats. Mathematically speaking, when the contestants make their first choice, there are two possibilities: they choose a goat or a car. Because there are goats behind the two doors, the probability of contestants choosing goats is 2/3; Accordingly, the probability of choosing a car is 1/3. At this time, the owner opened a door, and behind it was a goat. Let's assume that the contestants decide to change their choices. Then, if the contestant chooses a goat at first (2/3 possibility), then he will switch to a car; If a player chooses a car at first (1/3 possibility), he will switch to a goat. In other words, if the contestants change their choices, they will have a 2/3 chance to get a car. See if it is.