in summer在夏天；在夏季

last summer去年夏天；去年暑假

summer vacation暑假

hot summer炎热的夏天

summer holiday暑假

summer camp夏令营

summer day夏日

summer and winter夏和冬；经过整整一年；冬暖夏凉

early summer夏初

summer resort避暑地；避暑圣地

summer time n. 夏令时

summer night夏夜

summer season夏季

late summer晚夏

summer solstice夏至

summer school暑期学校

summer job暑假打工，暑期工作

summer rain夏雨

high summer盛夏

indian summer小阳春；兴旺的晚期；深秋初冬季节风和日丽的宜人气候