Example 1:

James: Oh my goodness, Lacy! What happened to your face? Your eye is black and blue! are you ok?
Lacy: Hi, James. Yes, I’m fine. I hurt myself yesterday at the park. I was roller skating and I fell over a stick. Can you believe it!?
James: Wow, you’re a really good skater, too. I hope it gets better soon. It looks bad!

Example 2:

Joe: I have a date tomorrow night after my big fight. I hope I win because I don’t want my face to be all black and blue for my date!
Pam: Well, Joe. You are a boxer. Being bruised is a normal part of your life! Besides, if she really cares about you, your face won’t matter!

Meaning:

to be black and blue means to be bruised.
A bruise is a dark mark that appears under your skin when you get hit or have an injury.

In the first example, Lacy’s eye is black and blue because she had an accident while roller skating and hit her face. So now, her eye is bruised. She has a bruise around her eye.

In the second example, Joe is a boxer. Many fighters experience injuries and their faces or bodies are often black and blue. Joe has a date and hopes his face won’t be bruised for his date.

This idiom is usually used as an adjective, so don’t forget the be verb!

This idiom comes from the LSI textbook “Speaking Savvy.” This book is used by LSI teachers in our Level 5 Speaking classes. For more information, please visit www.languagesystems.com