1,自行车曾经是中国城乡最主要的交通工具,中国一度被称为“自行车王国”。 Bicycles used to be main/major means of transport in China's urban and rural areas, for which China earned the reputation of "the bicycle kingdom". //看到地点,要想到用介词在……;前后两句要判断是否有并列,逻辑,和因果关系。