各种表示时间的短语和单词（如sunday,afternoon,festaval)前面分别要用什么介词

在某一天的早上、晚上、下午和不确定的时间段或较长的时间段、季节、月份时都用介词in ,比如: in the morning,in the afternoon, in the evening，in two hours,in two minutes,in two days,in two months,等等 .当用到具体的某一天时就用介词on , 比如: on sunday, on friday, on the 19th January.