进入到20世纪_____年代,我国旅游事业进入到全面发展阶段,出现了空前的繁荣。
While A(remembering) mainly B(for) the invention of the telephone, Alexander Graham Bell devoted his life C(to) D(helping the deaf).
Paul suggested that A(they meet) B(in the front) of the school gate C(at) one oclock D(Friday afternoon).
向旅游投诉处理机构请求保护合法权益的投诉时效期为_____天。