You can find the names of colors in a lot of English expressions. Many of these expressions, however, talk about colors in very different ways. For example, the expression black and white can have different meanings. If something is black and white, it means it is clear, easy to understand. However, some people see everything in black and white, which means that they judge everything they see as either good or bad. Some people must see something in black and white to know that it is true; This black and white talks about seeing something printed, as in a newspaper. If something is printed in a newspaper, it must be true, right?
Red is often used to talk about things that are hot or exciting. You can listen to red hot jazz music or eat red Hot Chili Peppers. If you roll out the red carpet for someone, you are giving them a big welcome. On TV, you may see stars walking on the red carpet at the opening night of a Hollywood movie or at the Academy Awards. If you do something embarrassing like spilled coffee on your teacher's desk, perhaps your face is beet red. Your teachers face might be red with anger, too! Or if you see a person doing something bad on purpose, like taking someone's wallet, you can say that you caught the person red handed whether it is good or bad, red usually means something interesting is happening.
Blue is different. When people are blue or have got the Blues, it means they feel sad. They might listen to Blues music, which usually tell sad stories. Blue is not always a sad color, though. If something good happens to you when you are not expecting it, like when you get a good idea or if you meet an old friend, you can say it happened out of the blue.
Learning New expressions with colors can be fun, but not always easy. As you can see their meanings can sometimes be very different. Try looking up these expressions in a good dictionary.
If you learn more about how these expressions are used, you may add a little color to your writing or even passed your next English test with success.