The break time was originally used to adjust the tense atmosphere of learning and allow students to relax physically and mentally. Some netizens recalled the "10 minutes between classes" of the past: some were chatting and laughing in the corridor

As a company that started out with playing cards

The card magic performed by Song Xiaobao required the audience to make a mark on the cards with a pen. A pen is needed to make a mark

Through the use of cards

Rummy is a classic cardgame where the objective is to be the first to get rid of all your cards, by creating melds, which can either be sets, three or four cards of the same rank, e.g. ♥8♠8♦8, or runs, which are three or more cards of the same suit in a sequence, e.g. ♥A♥2♥3. Aces are low, and sequences can not wrap around. There are many, many variations of Rummy that exist, this particular implementation is Basic Rummy, or Traditional Rummy.