Choose the correct variants.

1. They ... be lost. The are looking at the map. 2. They ... be in their home town, as they have lost their way. 3. They ... be tourists or overseas students. They have asked me the way to the main city attraction. 4. The weather ... be hot. It ... be summer. They are wearing warm clothes. 5. It ... be a big city. The population of the city is large.