长足进步

• 长(long hair; old person (pictographic))ASSOCIATIVE

An old person with long hair cascading down symbolizes something lasting a long time.

• 足(foot (pictograph))ASSOCIATIVE

A footprint drawing represents a foot and the act of walking.

• 辶(step; move)RADICAL
• 井(well; water well)PHONETIC

To advance forward like taking quick steps toward a well to get water.

• 止(foot (pictographic))RADICAL
• 止(second foot below)ASSOCIATIVE

A step is two feet, one above the other, following each other moving forward.