People often say that an Englishman's home is his castle. They mean that the home is very important and personal. Most people in Britain live in houses rather than in flats, and many people own their homes. They can paint and change them in any way they like. In a crowded city everyone knows that he or she has _ space that is only for himself or herself and for invited friends. People usually like to mark their space. Are you sitting on a beach or a train or in a library? If you are on the beach you may have spread your sands around you; on the train you may have put your coat or a small bag on the seat beside you; in a library you may have one corner or chair which is your own. Once I was traveling on a train to London. I was in a section for four people and there was a table between us. The man sitting opposite me had his bag on the table. There was no space on my side of the table at all. I was made rather angry. Maybe he thought that he owned the whole table! I took some newspapers out of my bag and put them on his. When I did this he sat up straight at once, opening his eyes wide. I had invaded his space! A few minutes later, I took my newspapers off his bag in order to read them. He at once moved his bag to his side of the table. The English call their homes "castles" because   _  .
they don't make friend with others they are very important persons they don't want to stay with others homes provide them with their own space