Use a tree diagram when the content has an obvious hierarchical structure, and use a table when multiple attributes of similar data need to be compared.

The tree diagram method is more hierarchical, such as three balls, 1 red and two black. Are there any ways to take it twice without putting it back? Here, two people take the ball, and the first result is the so-called "hierarchy" that has a direct impact on the second. It is more clear to express with tree diagram, and it is also conducive to thinking and doing problems (but it does not mean that list method cannot be used). List method is relatively more common. As long as you can list all the situations, a list or tree diagram is generally acceptable. The first is that there are too many possible events, and the list method is inefficient and time-consuming. The second involves geometric probability or non-discrete probability, such as choosing any real number from 0 to 10, and what is the probability greater than 5?