Can you remember the day when you spoke your first word? If you can, you are unusual. Try to imagine what the first few months of your life were like. I am sure you just spent most of your time eating, sleeping and crying.
As you grew older, you were awake more of the time. It took your parents more time to play with you and talk to you. You watched and listened curiously(好奇地). You began to know that people made certain sounds to go with certain things. Then you began to try making the sounds you heard.
And step by step, you were able to make the right sound for one thing. On that day you came to understand the secret of language: a certain sound means a certain thing.
When a group of people use the same set of sounds of things, they can understand each other. Then, and only then, these people have a LANGUAGE.
After you found the secret of language, you learned words. Some of the words meant things, such as BOOKS CHAIRS and SHOES. Some words meant doing things, such as GO and SWIM. And other words described things, such as GOOD and DIRTY. Soon you learned to put words together to express one's idea, such as "I want to go out and play with my friends. " This is language. By means of language, people can communicate.
So we say that languages are means of communication.