What word set completes the analogy chat and talk?

The analogy you've provided is based on synonyms. "Chat" and "talk" are both words for having a conversation.

Therefore, a word set that completes the analogy would be another pair of synonyms for conversation. Here are a few options:

* Converse and discuss

* Communicate and speak

* Dialogue and converse

All of these sets have words that are interchangeable in the context of having a conversation.