单词	mark/space frequency
释义	mark/space frequency 传/空号频率
随便看	the national groups the National Guard the National Guard and Reserve The National Guardsmen were sent out to trench the national health policy the national health service the National Health Service the national herald the National Hero the national high-tech development zone the national history the National Human Rights Action Plan of China the national hunt The National Identity the national idol the national image strategy the national immunization program the national innovation system the national institute for clinical excellence the national institutes of health the National Insurance act The national interest the national interests the National Islamic Front the Nationalist Government