对于星期，早上，年，和用时候介词用ON 还是 IN 的
热心网友
on weekday(Monday…) at weekendin the year in 2005in the morningon one day on 6th April,2005at some time at 6o'clock
热心网友
inthemorning(afternoon,evening,etc.)in(year). 2005...in(month). April...on(day,weekday).e.g.onMay1,2005,onSaturday,onweekends...at(time)(o'clock). 7:00pm,atnineo'clock(inthemorning,etc.)