一…就英语怎么说

"一" in English is usually translated as "one." Its origin comes from Old English "an," which evolved into "one" over time.
Examples in English:
I have one apple.
One plus one equals two.
He is the one I've been looking for.
中文翻译：
我有一个苹果。
一加一等于二。
他是我一直在寻找的人。