For an intended action, “plan to do” is standard. “Plan on doing” is also documented, with the gerund licensed by the preposition “on,” so it should not be simplified into a bare plan-doing versus plan-to-do choice.
ReviewedEvidence2 sourcesSectionEnglish Usage
Quick answer
Use “plan to do” for an intended action. “Plan on doing” is also standard, but the -ing form follows “on”; bare “plan doing” is not the same construction.
Key details
Confusion Familygrammar-and-usage distinction
Rule Familyverb complement pattern
TermsPlan Doing, Plan To Do
Further guidance
Decision
Prefer plan to do or plan on doing according to the sentence; do not substitute bare plan doing as though the forms were parallel.
Preposition Pattern
Plan on + -ing is also standard for intending or expecting an action; keep the preposition because it is part of the construction.
To Infinitive
Use plan + to-infinitive to state an intended future 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.
