Making friend is a skill. Like most skills, it improves with practice. If you want to meet people and make friends, you must be willing  to take some action. You must first go where there are people. You won't make friends staying home alone. Join a club or group, talking with those who like the same things you do is much easier. Or join someone in some activity. Many people are nervous when talking to new people. After all, meeting strangers means facing the unknown. And it's human nature to feel a bit uncomfortable about the unknown. Most of our fears about dealing with new people come from doubts about ourselves. We imagine other people are giving an opinion about us-finding us too tall or too short, too this or too that. But don't forget that they must be feeling the same away. Try to accept yourself as you are, and try to put the other person at ease . You'll both feel more comfortable. Try to keep self-confident even when you don't feel that way when you enter a room full of strangers, such as a new classroom, walk tall and straight, look directly at other people and smile. If you see someone you'd like to speak to, say something. Don't wait for the other person to start a conversation. Just meeting someone new does not mean that you will make friends with that person-friendship is based on each other's liking and "give and take". They take time and efforts to develop. And there are things that keep a new friendship from growing. In the sentence "After all, meeting strangers means facing the unknown.", the word "unknown" means   _  .
without somebody knowing without somebody liking unfriendly unpleasant