You'll Be 'Sharp as a Tack' with These Expressions
There are many ways to describe smart people. For example, they can be called "bright" or "sharp." Someone who is "as sharp as a tack," for example, is very clever and a quick thinker.
It's not very nice to call someone "dumb", however. So English speakers often use idioms to describe such people. For example, someone who is "not the sharpest tool in the shed" is not very smart.
Someone who is "book-smart" knows a lot about different subjects from studying. You can also describe them as a "walking encyclopedia" — just like an encyclopedia, they seem to have information about everything.
Other people may not read much, but have learned a lot from real-life experiences. Such a person is called "street-smart."
If someone doesn't know something, then they are "ignorant" of it. For example, "John is a great artist, but he is ignorant when it comes to math and science."
In English, the expression "ignorance is bliss" means that if you don't know about something, you don't worry about it. For example, "Bill never watches the news, because he believes that ignorance is bliss."
However, the opposite is often true: the more you know, the better off you are. This idea is expressed by the common expression, "knowledge is power."
