A．Kings and queens, princes and princesses, and lords and ladies built castles in order to get more land.
B．Around the outside of a castle, a moat was dug, which was often filled with water.
C．A castle was built behind a thick and high stonewall, which was strong enough to stand the possible attack of enemies.
D．If a drawbridge was pulled up, there was no way for people to enter the castl