per day的用法和樣例：
例句
- The salary of a hireling is 6 pounds per day.
僱工一天的工資是六鎊。 - London have on average7.6 hours of sunshine per day during May.
倫敦五月份每天平均有7。6小時日照時間。 - The travelling expenses work out at12 dollars per day each.
計算的結果，每天人每天的旅費是12美元。 - The room rate at this motel range from$30 to$50 per day.
這個汽車旅館的房價每天從三十美元到五十美元不等。
