A1during part or all of a period of time: We're going to Italy in April.Some trees lose their leaves in (the) autumn.I started working here in 2009.Life in the 19th century was very different from what it is now.Bye, see you in the morning (= tomorrow morning).She was a brilliant gymnast in her youth (= when she was young).How many civilians died in the Vietnam War?This is the first cigarette I've had in three years.I haven't had a decent night's sleep in years/ages (= for a long time).Describing when something happened or will happenIn and atin between›between the two times mentioned: I have breakfast at 7.30, lunch at 1.00, and sometimes a snack in between.Between