Existence. The validity period of one-on-one private swimming lessons is in accordance with the law, because most private swimming lessons are divided into one-year courses and lifelong courses, and students can choose by themselves in the process of signing contracts. Private education courses are private institutions, and these private education institutions need to recruit more students to make money. If every student can attend classes for life, the profit of the institution will be less and less, and eventually it may close down because there are no students. Therefore, most private education courses will set a validity period, so that students can.