Be Thankful To Do vs. Thankful For Something distinguishes two directly documented complement patterns for the adjective “thankful.” Use thankful + to-infinitive for the directly documented infinitival construction; use thankful for + noun phrase for the separately documented prepositional construction. The page stays within those attested patterns and does not infer a broader rule from synonymy.
ReviewedEvidence1 sourceSectionEnglish Usage
Quick answer
Use thankful + to-infinitive when the adjective takes its documented infinitive complement; use thankful for + noun phrase when the complement is introduced by the documented preposition.
Key details
Confusion Familyadjective-complement
Rule Familyadjective complementation
Termsthankful + to-infinitive, thankful for + noun phrase
Choose the right form
Decision table for Be Thankful To Do vs. Thankful For Something
Meaning / situation
Construction
Decision
gratitude linked to an opportunity or event expressed as an infinitive
thankful + to-infinitive
use the reviewed infinitive pattern
gratitude for a named person, thing, event, or circumstance
thankful for + noun phrase
use “for” to name what prompts gratitude
Quick tests
Opportunity-or-object test
Are you expressing gratitude through an event/opportunity, or naming what you are thankful for?
If yes: Use “thankful to + verb.”
If no: Use “thankful for + noun phrase.”
Caveat: This is a complement distinction; it does not rank one form as more sincere or more formal than the other.
Examples
Example
We were thankful to receive an early warning.
The infinitive presents the event associated with gratitude.
Example
We were thankful for the extra time.
“For” names the thing prompting gratitude.
Example
She was thankful to attend and thankful for the invitation.
The example contrasts event with object.
Further guidance
Core difference
Use thankful + to-infinitive for the directly documented infinitival construction; use thankful for + noun phrase for the separately documented prepositional construction.
Style Boundary
Treat this as a comparison of directly documented complement patterns, not as a claim that every other complement is impossible. Choose the construction that matches the intended grammatical 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.
