Be Horrified To Do vs. Horrified At Something distinguishes two attested complement patterns for the same adjective. Use horrified + to-infinitive for the adjective followed by its documented complement pattern; use horrified at + noun phrase for the separately documented construction. The constructions are not interchangeable simply because they share the adjective; choose the pattern that matches the grammatical relationship you mean.
ReviewedEvidence1 sourceSectionEnglish Usage
Quick answer
Use horrified + to-infinitive when the adjective introduces that documented complement; use horrified at + noun phrase when you mean the second documented relationship.
Key details
Confusion Familyadjective-complement
Rule Familyadjective complementation
Termshorrified + to-infinitive, horrified at + noun phrase
Choose the right form
Decision table for Be Horrified To Do vs. Horrified At Something
Meaning / situation
Construction
Decision
horror linked to discovering, seeing, hearing, or another event
horrified + to-infinitive
use the infinitive to present the event
horror directed toward a thing, condition, or fact
horrified at + noun phrase
use “at” to name the object/cause
Quick tests
Event-or-object test
Are you presenting the event that prompts horror, or naming the thing at which someone is horrified?
If yes: Use “horrified to + verb” for the event.
If no: Use “horrified at + noun phrase” for the object or circumstance.
Caveat: The comparison is limited to the reviewed complement patterns.
Examples
Example
We were horrified to discover the error.
The infinitive presents the discovered event.
Example
She was horrified at the damage.
“At” introduces the object or circumstance prompting the reaction.
Example
He was horrified to hear what had happened.
The infinitive introduces the reported event.
Further guidance
Core difference
Use horrified + to-infinitive for the adjective followed by its documented complement pattern; use horrified at + noun phrase for the separately documented construction.
Style Boundary
Treat the distinction as a complement-pattern choice, not as a claim that every nearby preposition or clause is impossible. Follow the directly documented construction for the intended relationship.
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.
Be Afraid To Do vs. Afraid Of Something distinguishes two directly documented complement patterns for the adjective “afraid.” Use afraid + to-infinitive for the directly documented infinitival construction; use afraid of + noun phrase for the separately documented prepositional construction. The page stays within those attested patterns and does not infer a broader rule from synonymy.
Be Alarmed To Do vs. Alarmed At Something distinguishes two directly documented complement patterns for the adjective “alarmed.” Use alarmed + to-infinitive for the directly documented infinitival construction; use alarmed at + noun phrase for the separately documented prepositional construction. The page stays within those attested patterns and does not infer a broader rule from synonymy.
Be Amused To Do vs. Amused By Something distinguishes two directly documented complement patterns for the adjective “amused.” Use amused + to-infinitive for the directly documented infinitival construction; use amused by + noun phrase for the separately documented prepositional construction. The guide stays within those attested patterns and does not infer a broader rule from synonymy.
Be Annoyed To Do vs. Annoyed About Something distinguishes two directly documented complement patterns for the adjective “annoyed.” Use annoyed + to-infinitive for the directly documented infinitival construction; use annoyed about + noun phrase for the separately documented prepositional construction. The page stays within those attested patterns and does not infer a broader rule from synonymy.
Be Astonished To Do vs. Astonished At Something distinguishes two directly documented complement patterns for the adjective “astonished.” Use astonished + to-infinitive for the directly documented infinitival construction; use astonished at + noun phrase for the separately documented prepositional construction. The page stays within those attested patterns and does not infer a broader rule from synonymy.
Be Astounded To Do vs. Astounded By Something distinguishes two directly documented complement patterns for the adjective “astounded.” Use astounded + to-infinitive for the directly documented infinitival construction; use astounded at/by + noun phrase for the separately documented prepositional construction. The guide stays within those attested patterns and does not infer a broader rule from synonymy.
