自由 (zì yóu) is the general word for 'freedom' — both as a noun (freedom, liberty) and an adjective (free, unrestricted). It contrasts with 自在 (zì zai), which describes a personal feeling of ease and comfort, not political or structural freedom. 任意 (rèn yì) means 'arbitrary' or 'at will', often with a negative connotation of doing something without limits.