本来用英语的说法是 "originally" 或 "initially"。这两个词都有类似的意思，都表示"原本"、"本来"的意思。

来源：

originally 是由英语单词 "origin" 和词后缀 "-ally" 构成的。"origin" 意为 "起源"，"-ally" 是一个后缀，表示"方式"、"方式"等意思。因此，"originally" 的意思就是 "在起源上"、"原本" 等意思。

initially 是由英语单词 "initial" 和词后缀 "-ly" 构成的。"initial" 意为 "开头的"，"-ly" 是一个后缀，表示"方式"、"方式"等意思。因此，"initially" 的意思就是 "在开头上"、"原本" 等意思。

例句及其中文翻译：

Originally, I was going to go to the store, but then I realized I didn't need anything. 原本，我要去商店，但后来我意识到我什么都不需要。

Initially, I thought the project would be easy, but it turned out to be much more difficult than I expected. 最初，我以为这个项目很简单，但实际上它比我想象的难得多。

The company was founded in Chicago, but it has since moved its headquarters to New York. 原本，这家公司在芝加哥成立，但现在它已经把总部迁到了纽约。

I was initially skeptical about the idea, but after thinking about it more, I realized it might actually be a good idea. 最初，我对这个想法持怀疑态度，但经过更多的思考，我意识到它可能是个好主意。