Keep + person + -ing describes causing or allowing an activity to continue. Keep + person + to-infinitive is not the corresponding ordinary continuation pattern.
ReviewedEvidence1 sourceSectionEnglish Usage
Quick answer
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
Confusion Familygrammar-and-usage distinction
Rule Familyverb-complement and object pattern
TermsKeep Someone Doing, Keep Someone To Do
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.
Cambridge documents keep + person/thing + from + -ing for prevention. “Keep someone to do” is not the parallel prevention pattern and needs a different structure or meaning.
Oxford directly documents “argue somebody into doing something” for persuading somebody by giving reasons. The cited construction evidence directly supports into + -ing; it does not license “argue someone to do” as an equivalent complement pattern.
When ask means request an action from a person, Cambridge documents ask + person + to-infinitive. Bare “ask doing” is not the ordinary request complement for that meaning.
Cambridge directly documents both badger + object + into + -ing and badger + object + to-infinitive for repeated pressure or requests that push someone toward an action. The verb also covers repeated questioning, so context must show whether the sentence is about persistent persuasion or interrogation rather than assuming every use names a requested action.
Cambridge directly illustrates bamboozle + object + into + -ing for deceiving someone so that the person takes an action. The cited entry does not establish bamboozle + object + to-infinitive as an equally documented alternative, so this guide does not manufacture a two-way rule.
Cambridge explicitly documents beg + object + to-infinitive for an urgent request and also records beg for + noun and other request patterns. A following -ing form may appear elsewhere in a sentence, but it is not the ordinary replacement for the documented object + to-infinitive request construction.
