Oxford documents both consent to something and consent to do. That distinction explains why an -ing form can follow prepositional “to” while the direct action pattern uses the to-infinitive.
ReviewedEvidence2 sourcesSectionEnglish Usage
Quick answer
Use “consent to do” when someone agrees to perform an action. In “consent to doing,” the **to** is a preposition and the -ing form names the thing consent is given to; bare “consent doing” is not the standard pattern.
Key details
Confusion Familygrammar-and-usage distinction
Rule Familyverb complement pattern
TermsConsent Doing, Consent To Do
Further guidance
Decision
Distinguish infinitival “to” in “consent to do” from prepositional “to” in “consent to doing”; do not omit the preposition before the gerund.
Prepositional To
In consent to + noun/-ing, “to” is a preposition introducing the matter or activity being agreed to.
To Infinitive
Use consent + to-infinitive when someone agrees to perform the following action.
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.