Activity: Fill in each blank with a suitable preposition. 1.Which companies was she referring ___when she spoke of competing firms? 2. Bats communicate___ each other by ultrasonic messages. 3. Citizens may have free access ____the library. 4. It is rude to mock ____others’ shortcomings. 5.I’d like to go back to teaching, but I am ___ touch with my subject now. 6. She is determined to do regardless ____all consequences. 7. Food is essential ___ life. 8. At the time, many doctors had serious misgivings ____ the new treatment. 9. Any climber who neglects these simple precautions does so___ his peril.