Before revision: Conversational Machine Comprehension (CMC) is a research track in conversational AI which expects the machine to understand an open-domain  text and thereafter engage in a multi-turn conversation to answer questions related to the text.
After revision: Conversational Machine Comprehension (CMC) is a research track in conversational AI which expects the machine to understand an open-domain natural language text and thereafter engage in a multi-turn conversation to answer questions related to the text.