There is one language that is used in every country in the world. The people who use it are young and old, short and tall, thin and fat. It is everybody's second language. It is easy to understand, although you can't hear it. It is sign  language. When you wave to a friend who is across the street, you are using sign language. When you smile at someone, you are saying, "I want to be friendly", but you are not using speech. You are using body language. When you raise your hand in class, you are saying, "Please ask me. I think I know the correct answer." Babies who can't talk can point at things. They are using sign language. A policeman who wants to stop traffic holds up his hands. He is using sign language. Many years ago, a French priest, Charles Michel de Epee, became interested in education for deaf people. He invented a finger alphabet  . It is still in use. People can make the sign  for letters and spell words with their hands, and deaf people can read and understand them. Soon there were schools for the deaf in many countries. The only university for the deaf is Gallaudet College in Washington, D.C. Today, in the United States, there are special TV news programs for deaf people. The newsreader tells the news in sign language. At the same time, the words appear on the TV screen. The actors in the Theatre of Deaf don't spell every word. Sometimes they use hand signs. When they put two hands together, it means sandwich. They can make a roof with their hands when they want to show a house. One finger in front of an actor's mouth can mean quiet. You can talk to people who are behind windows that are closed. And when you go swimming with your friends, you can have conversations under water. How many hand signs do you use every day? If you want to express the idea that "I am very friendly" to someone, you will   _  .
raise your hand put one hand onto the other smile to the person make a roof with your hands