Complete each statement with a word in blue from exercise A. 1. Humans can't survive a long without sleep. The record is 11 days. 2. The region was in the middle of a terrible drought. , it rained last week. 3. One of the that astronauts face is living in a small space. 4. If you want to become an astronaut, you cannot be afraid of heights. 5. The in Antarctica are hostile, but penguins can live there. 6. If you are to some chemicals, you may become ill. 7. One we are facing is global warming. 8. Animals must to changes to their habitats or become extinct. 9. The the teacher used was effective. Her students did well on their exams. 10. The job of an astronaut can be very , but also very exciting.