吃野餐用英语可以说是"have a picnic". "Picnic"这个词源自法语词汇"pique-nique"，其本意是指拿一个尖锐的东西（如尖刀或叉子）去刺（piquer）食物。在18世纪，"picnic"开始被用来指"公共野餐"，并逐渐演变为今天常见的"与家人或朋友到户外野餐"的意思。

例句：

我们明天去公园里吃野餐吧。

Let's have a picnic in the park tomorrow.

你们打算在哪里吃野餐？

Where are you planning to have your picnic?

他们在河边野餐时遇到了一场暴风雨。

They had a picnic by the river, but they were caught in a storm.