Advanced Conversation "401" requires skill and practice. This is a technique of almost infinite volleying.
Inevitably a subject matter in the conversation begins to wane - "run out of gas". In tennis the volleys become weaker and harder to hit. If you are unprepared silence hits and both players stand stunned without a clue of where the subject ball has landed. Without the ball (new subject) there is no chance of play.
A great conversationalist can anticipate this and spin the subject into a brand new conversational volley. The key to this technique is careful listening to associated subjects casually refereed to by the other player. Example:
Suppose you served up the vacation subject: "Where are you going to vacation this summer?" During the volley of responses the other player mentions the challenges of air travel to Europe. As the subject begins to fade you might ask: "What do you do to try to avoid jet lag?" or "What's you favorite and least favorite Airline? (nearly everyone will have a slew of travel stories).
Once you start spinning into new subject manners your conversational partner may start spinning subjects back. This can be a very enjoyable advanced game.