题目

    Anne lived in Amsterdam in the Netherlands during World War II. Her family was Jewish so they had to hide  61  they would be caught by the German Nazis. They hid away for nearly 25 months before they were discovered. She suffered from  62  (lonely). There was a time  63  the only true friend was her diary. She kept a diary  64  (set) down her experiences. One evening when it was warm, she stayed awake  65  purpose until half past eleven to look at  66  moon by herself. Another time when it was rainy, she didn’t go downstairs until the window had to be shut. The dark如图所示，已知：在△ABC中，∠ACB=90°，CD⊥AB，∠A=30°，AB=12cm，则BD= cm．