江苏省南通市2014
高考英语阅读理解、短文改错训练(6)(答案或解析) today about 70 countries use daylight saving time (dst). daylight saving was first introduced during world war i in australia. during the world wars, dst was used for the late summers beginning january 1917 and 1942, and the full summers beginning september 1942 and 1943.