As a verb, risk takes an -ing complement for an action that may lead to a bad result. Cambridge gives examples such as “risked losing,” so the reviewed direct pattern is “risk doing,” not “risk to do.”
ReviewedEvidence2 sourcesSectionEnglish Usage
Quick answer
Use “risk doing” when the action itself is exposed to a possible bad result: “risk losing,” not direct “risk to lose.”
Key details
Confusion Familygrammar-and-usage distinction
Rule Familyverb complement pattern
TermsRisk Doing, Risk To Do
Further guidance
Boundary
Risk can also take a noun object, but that does not license a direct to-infinitive as a parallel complement.
Construction
Cambridge documents risk + -ing verb for doing something despite the possibility of a bad result.
Decision
Choose “risk doing” for the direct verbal complement.
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 both admit + -ing and admit to + -ing for acknowledging something. Other passive patterns such as “be admitted to be” are separate constructions.
Both patterns are standard. “Advise waiting” recommends an action generally or in context, while “advise him to wait” names the person who is advised to perform it. A that-clause is another standard option.
When “afford” is followed directly by another verb, standard learner references use a to-infinitive: “afford to do.” An -ing form can appear elsewhere in a sentence, but it is not a like-for-like direct complement after “afford.”
“Agree to do” expresses consent to take an action. An -ing form normally follows a preposition in patterns such as “agree with doing,” which expresses approval rather than the direct promise-to-act construction.
Cambridge documents aim + to-infinitive for intention and aim at for directing effort toward an objective. Do not omit the preposition and present bare “aim doing” as equivalent to “aim to do.”
“Allow” can take an activity as its object, as in “allow smoking,” or a person/thing followed by a to-infinitive, as in “allow visitors to enter.” The patterns answer different structural questions: what is allowed versus who is allowed to do what.
