Use 'run into' when you unexpectedly meet someone you know.

Social Surprise

'Run into' is often neutral but can be positive or negative based on who you meet.

Neutral Context

'Run into' frequently happens in places where people gather, like malls or events.

'Run into' indicates unexpected problems, not ones you're prepared for.

Problems you 'run into' can be minor hiccups or major roadblocks.

'Run into' can mean an actual impact, generally referring to accidents.

Use 'run into' for accidental collisions, not intentional actions.

Use 'run into' when costs are unexpectedly high or accumulate quickly.

'Run into' suggests reaching large or surprising amounts, often unplanned.