O que significam as expressões "begin to see the light" e "to see the light at the end of the tunnel"?

You're attending a Math class on a very difficult topic and you couldn't be more confused. During break time, you come across your friend at the hallway and you tell him how frustrated you are for being at such a total loss with this new topic. He tells you he didn't have much trouble understanding it and that if you wanted he could help you out by giving you private one-on-one lessons. After some of these lessons with your friend, you begin to see the light after his explanations.

When you begin to see the light, it means you're starting to understand something. Be careful not to mistake that expression for a very similar one: to see the light at the end of the tunnel. In that case, when you see the light at the end of the tunnel, it means you feel hopeful after a lot of struggling, you can finally foresee an end to your problem. So imagine you've been ill for a long period of time and then one day you wake up feeling way better. That's when you say you can see the light at the end of the tunnel, because you're full of hope again. Those are the two expressions of the day. I hope you enjoyed them. Take care!