Why was there a da-zi written for Ji-li?

At school, Ji-li is asked to write a da-zi-bao, or a poster that criticizes an element of society that is anti-revolutionary during the Cultural Revolution. Several of her friends criticize her teachers, including for buying bread for a student who had forgotten lunch. This is seen as an attempt to corrupt the student.

Explanation:

- "the die is cast; i have consented to return if we are not destroyed. thus are my hopes blasted by cowardice and indecision; i come back ignorant and disappointed. it requires more philosophy than i possess to bear this injustice with patience. i have lost my hopes of utility and glory; i have lost my friend."

there mad at that place