第一节语法和词汇知识(共15小题；每小题0．5分，满分7．5分)
21．Don\'t be scared．A chain was           to the dog\'s collar by its owner．
   A．kept     B．united     C．stuck  D．attached
22．You can take as many books as you like here because they are free of        ．
   A．charge     B．fare     C．money  D．pay
23．-Will your brother come for dinner tonight?
  -          ．He has promised me．
   A．Never     B．Eventually     C．Definitely  D．Unfortunately