1. The dog guarded the house against strangers. �����ŷ��ݣ�����İ���˽�ȥ��
2. From afar, this piece of green bamboo as a barrier, like the green rows of guards, guarded in silence next to the stream. ԶԶ��ȥ��������һƬ������һ�����ϣ�����һ������ɫ��������ĬĬ���������Աߵ�СϪ��
3. THE PRESIDENT:First, let me condition the press this way. Any sources and methods of intelligence will remain guarded and secret. ��ͳ�����ȣ��һ��Դ˷�ʽ�ٿ������д��ᡣ�鱨���κ���Դ����ʽ���ᱣ�ֽ����ͻ��ܡ�