1. You should take the train instead of the bus. -> If................................................ .................................................. .................. 2. I'm sure that someone forgot to lock the door. --> Someone must.............................................. ................................................. 3. They bought this house ten years ago. --> They have.............................................. .................................................. ..... 4. The course finished with a big party. --> At the end............................................... .................................................. .... 5. We invited a pop star onto the chat show, but he didn't turn up. --> The pop star.............................................. .................................................. ..