"Expose" means to show something that was once hidden. Imagine a toy you can't see because it's inside a box. You can't play with it until someone takes the lid off the box and shows you the toy. That's what "expose" means - to show something that was hidden before. It could be a secret or a problem that people didn't know about, but someone decides to tell everyone what's really happening. They want to make sure everyone knows what's going on so that they can fix the problem or make it better. It's like revealing a surprise or a mystery to the public.