Reply / Answer / Revert
Regional usageReply normally takes to before the person or message; answer normally takes its object directly. Revert meaning reply is familiar in Singapore workplaces, but reply is clearer for an international audience.
Reply
Use when
You give a spoken or written response to a person or message; use reply to before the recipient or message.
Example
“Please reply to the secretariat by Friday if you have comments.”
Answer
Use when
You respond to a question, email, call or person and place the object directly after the verb.
Example
“Please answer the question in paragraph 12.”
Revert
Use when
You mean reply in a variety of English where that regional sense is established and familiar.
Example
“Please revert with the cleared figures by Friday.”
Quick check
reply me by Friday, answer to the question, revert back, revert used where return to a previous state could be understood
Usage note
Revert also means return to a previous state or practice. Do not label the regional reply sense as inherently wrong, but avoid the redundant revert back. Write reply to me and answer the question.