Grammar fix
go back on
not do something you promised or agreed to do
to break a promise or agreement; to decide not to do something you said you would do.
phrasal verbB2common
Hear it in context
Notice where the phrase sounds natural.
- He promised to help me move, but then he went back on his word at the last minute.relationships
- In my opinion, it's important not to go back on your promises, especially when working in a team.IELTS speaking
Fix the pattern
Pattern: go back on + (one's) word/promise/agreement
WrongDon't go back your promise.
RightDon't go back on your promise.
Needs 'on' — 'go back ON a promise / your word / the deal'.
Patterngo back on + (one's) word/promise/agreement
Use it right
Choose the version that sounds natural in speech.
'Go back on (your word/promise)' is the idiomatic phrase. 'Failed to honour his commitment' is formal/legal.
Build natural chunks
Words that usually travel with it.
go back on + commitmentyour worda promisethe dealan agreement
Don't confuse it
'Go back to' means to return to a place or situation, not to break a promise.