Keep Someone Doing vs. Keep Someone To Do
Keep + person + -ing describes causing or allowing an activity to continue. Keep + person + to-infinitive is not the corresponding ordinary continuation pattern.
Use “keep someone doing something” for an activity that continues. Do not treat “keep someone to do something” as an interchangeable complement pattern.
Key details
Choose the right form
| Meaning / situation | Form / construction | Decision |
|---|---|---|
| cause a person to remain engaged in an activity | keep + person + -ing | Use “keep someone doing.” |
| assume person + to-infinitive expresses the same continuing activity | keep + person + to do | Do not use this as an interchangeable complement. |
Quick tests
Meaning / construction test
Do you mean that a person remains engaged in an ongoing activity?
If yes: Use “keep + person + -ing.”
If no: Recast if you mean a purpose or future task rather than continuing activity.
Caveat: Other “keep” constructions exist; this page isolates the person-plus-continuing-activity pattern.
Examples
The extra questions kept us talking after the meeting.
The people remain engaged in the activity.
A delay kept the crew waiting outside.
The object is followed by an ongoing -ing activity.
The puzzle kept the children guessing.
The construction expresses a continuing state/activity.
Further guidance
Boundary
Keep has separate senses such as retain, store, remain, and keep someone from doing something; those use different complements.
Construction
Cambridge documents keep + -ing for continuing or repeatedly performing an activity.
Decision
Choose object + -ing when the person remains engaged in the activity; recast when you mean retain someone for a future task.
Sources and evidence
Sources are shown with the role they play in this guide. Historical or style-sensitive claims are kept within the evidence boundary described above.
- keep — Cambridge Dictionary (opens in a new tab)Cambridge Dictionary · Keep + -ing for continuing or repeatedly doing an activity