四大

sì dà

ㄙˋ ㄉㄚˋ

1the four elements: earth, water, fire, and wind (Buddhism)

2the four freedoms: speaking out freely, airing views fully, holding great debates, and writing big-character posters, 大鸣大放|大鸣大放, 大辩论|大辩论, 大字报|大字报 (PRC)

Characters

四大