曾经是盛夏怎么说英语

"Once upon a summer" is a phrase that could be used to describe a time that was once summer. In this context, "once" means "at one time" or "in the past," and "upon" means "at or during." "Summer" refers to the warmest season of the year, which is typically associated with long days, warm weather, and outdoor activities.

Here is an example of how this phrase might be used in a sentence: "We used to spend every summer at the beach, but now those days are just a distant memory. Once upon a summer, we would spend our days swimming and building sandcastles, and our nights roasting marshmallows over a campfire."