Do you know the history of the English dictionary? The first English dictionary came out in 1604. The dictionary was nothing but a list of about 3,000 difficult words together with a one-word definition (解释). The writer, Robert Cawdrey, didn't put everyday words in his dictionary. He said no one would ever have to look up a word in a dictionary if he already knew the meaning of the word. Since then many kinds of dictionaries came out. But they were all like Robert's.
A man named Dr. Samuel Johnson changed all this. Dr. Johnson wrote the first modern dictionary. And it came out in 1755. He put all important words in his dictionary, both easy and hard, and he told clearly what the words meant. He also gave good sentences to show how each word was used in spoken English and in written English. From then on, dictionaries were getting better and better.
The dictionaries we use today are nearly all like Dr. Samuel Johnson's.