‘塞进’ is a compound verb meaning 'to shove in' or 'to cram in'—it emphasizes forceful, often hurried or tight insertion of something into a space. The first character 塞 (sāi) means 'to stuff' or 'to block', and the second 进 (jìn) means 'in' or 'into'; together, they form a directional verb complement structure where 塞 is the main action and 进 indicates the direction of movement. This word implies physical pressure, limited space, or urgency—and is commonly used with objects like papers, food, clothes, or small items.

It’s frequently heard in everyday spoken Chinese, especially when describing actions involving containers, pockets, bags, drawers, or tight openings. Unlike neutral verbs like 放进 (fàng jìn, 'to put in'), 塞进 carries a connotation of effort, lack of room, or informality. It can also be used figuratively in casual speech—for example, to describe hastily inserting information into a conversation—but literal physical usage dominates.