原来 yuánlái
原来（yuánlái）means “so it turns out; originally”. "原来" has two uses. Formation: 原来 + 句子（发现真相）/ 原来 + 名词·状态（原先）
so it turns out; originally
HSK4Formation
原来 + 句子（发现真相）/ 原来 + 名词·状态（原先）
Explanation
"原来" has two uses. First, it signals a sudden realization of the truth: "so it turns out…" Second, it means "originally / formerly," describing a previous state that has since changed.
Examples
原来是你啊，我还以为是别人呢。
yuánlái shì nǐ a, wǒ hái yǐwéi shì biéren ne
Oh, so it's you — I thought it was someone else.
他原来住在北京，现在搬到上海了。
tā yuánlái zhù zài běijīng, xiànzài bāndào shànghǎi le
He originally lived in Beijing; now he's moved to Shanghai.
Note
"原来如此" is a set phrase: "ah, I see / so that's how it is."
FAQ
原来 — what does it mean and how is it used?
so it turns out; originally. "原来" has two uses. First, it signals a sudden realization of the truth: "so it turns out…" Second, it means "originally / formerly," describing a previous state that has since changed.
原来 — how do you form it?
原来 + 句子（发现真相）/ 原来 + 名词·状态（原先）
原来 — any usage notes?
"原来如此" is a set phrase: "ah, I see / so that's how it is."