The couple chose one of two categories and took turns answering a series of questions, using one of three response choices. The clock began to run when the first question was asked; if the couple gave the required number of correct answers, the clock stopped and they chose a new category to play the next higher level.
The couple picked one of two categories and took turns answering a set of questions, each with three possible responses. The clock started when the first question was asked; if they answered correctly enough, the clock would stop, and they'd move on to the next category at a higher level.