(2) "Enlightenment in Geleshan and Zen in Zhatu Cave" means persisting in studying and understanding the revolutionary truth of Marxism-Leninism in the enemy's prison. The banner "Elysium" expresses the optimism of revolutionaries in mastering revolutionary truth.
(3) Looking at the cave is still the same, and looking out the window is the Spring Festival. The "old scene" refers to the rule of the Kuomintang reactionaries, and the "New Year" refers to the prospect that the revolution will soon win in the whole country. Together with the banner "All difficulties are coming", it expresses the revolutionaries' belief in the imminent victory of the revolution and their vision for the future of the revolution.
(4) Spring can't be caged in the garden, and an almond goes out of the wall: to borrow an ancient poem, it not only expresses contempt for reactionaries (it is futile to stop the revolutionary victory), but also expresses hope for victory (an almond goes out of the wall). The banner of "Returning in Spring" vividly summarizes the revolutionary situation at that time.
⑤ Two skylights-vent and damper-protrude. This couplet summarizes the inhuman life of revolutionaries in prison. Gene's "Enjoying in it" expresses the revolutionary feelings of revolutionaries who take pleasure in suffering, and it is also a clever exposure of reactionaries persecuting revolutionaries.
It expresses the revolutionaries' contempt for the dark forces and their confidence in the victory of the revolution. Revolutionaries know that the day will come soon when the people are masters of their own affairs. For the victory of the revolution, they greeted this beautiful day with laughter and parties!