in holiday 泛指放假,但說話人說話的時候并不在放假.如,i'd like to stay with my families in holiday.in the holiday 指特定的假期,根據上文的延續.如,Christmas is a spcial holiday in western countries.In the holiday,people usually stay with their families.on holiday 處于放假的狀態如,i'm on holiday now.類似有on duty 上班中幫你造了幾句話,你可以通過理解句意來看區別,希望對你有用on the holiday:A few more traveller's cheques may come in handy on the holiday.多帶幾張旅行支票,度假時會有用的.in the holiday:we (enjoy ourselves) in the holidays.In the holiday season one finds the trains unpleasantly full of people.節日期間,人們可以看到火車上擁擠不堪,人滿為患.如果你前面曾經提起過某個節日,而現在針對這個節日說on,就要用on the holiday,特指在這個節日.否則,用on holiday