"Summer vacation" in Engpsh is pronounced as "sʌmər vəˈkeɪʃ(ə)n"（中文读音为"sʌmər vəˈkeɪʃ(ə)n"）.

"Summer" comes from Old Engpsh "sumer", which refers to the season of the year that is typically the warmest and most pleasant. "Vacation" comes from the Latin word "vacatio", which means "leisure, freedom from work, or a period of time devoted to rest or pleasure".

Examples:

"I can't wait for summer vacation to start." (我等不及夏假开始了)
"I'm planning a trip for my summer vacation." (我正在为夏假计划一次旅行)
"During summer vacation, I pke to relax at the beach." (在夏假期间，我喜欢在海滩上放松)