Mergers, acquisitions, coworkers coming and going... there are a multitude of changes that can occur at work. You will need to be well equipped to change and adapt to your environment.
"My supervisor got promoted and was replaced with someone who was not very prepared to take on the responsibility. It affected my work, because she was often asking me for my opinion and for help understanding things. I had to draw clear boundaries and let her know that she needed to talk to her higher up if she has issues so that I can focus on my research."