that is (to say) said when you want to give further details or be more exact about something 那就是说;换句话说 I'll meet you in the city, that is, I will if the trains are running. 我们城里见，那就是说，只要火车还开我就会见到你。 That would mean voting no, that is to say, using the veto. 那就意味着投反对票，也就是说，行使否决权。