(1) Suchahas is generally used to list several examples of similar people or things, inserted between the listed examples and the previous nouns, and there is no comma after as. When using Suchahas, we should pay attention to the fact that the number of things listed behind cannot be equal to the sum of the things mentioned above. If they are equal, use either or. For example:

He has been to many countries, such as America, Japan and Germany. He has been to many countries, such as America, Japan and Germany.

(2)example generally takes only one person or thing of the same kind as an example, which can be placed at the beginning, middle or end of a sentence. For example:

For example, air is invisible. For example, air is invisible.

For example, he is a good student. For example, he is a good student.

(3) that is derived from Latin, which is the abbreviation of id est. It means "in other words", which is equivalent to "in other words" and "namely" to further illustrate the above point.