未开英语怎么说

"未开" 的英文表达是 "unopened"。
这个词来源于英语中 "un-" 和 "open" 的组合，"un-" 是否定前缀，"open" 意为 "开启"。
例句：
The package was unopened when I received it. (我收到时包裹是未开的。)
I like to keep my books unopened until I'm ready to read them. (我喜欢在准备阅读时再打开书。)
The unopened bottle of wine was still good after a year. (未开的酒瓶在一年后仍然饮用。)