所以
so; therefore; that's why
suǒyǐ
What does 所以 mean?
所以 (suǒyǐ) is the conjunction 'so / therefore / that's why' — it introduces the result or conclusion of a stated cause. The signature pattern is 因为 X，所以 Y ('because X, so Y'), and unlike English (which usually drops one half), Chinese commonly keeps BOTH halves: 因为下雨，所以我没去 = 'Because it was raining, (so) I didn't go.' English speakers often instinctively delete 'so,' which sounds incomplete in Chinese. 所以 can also stand on its own without 因为, simply marking the conclusion: 我累了，所以我要睡觉 ('I'm tired, so I'm going to sleep').
In casual speech, 所以呢？ ('so what?' / 'and?') is a common follow-up. The character 所 alone has many meanings, but in 所以 it functions as a fixed conjunction — don't try to translate piece by piece.
Note: Standard conjunction in speech and writing. Often paired with 因为
Character breakdown
place; that which; (grammatical particle)
to; with; by means of
Memory hook: 所以 literally hints at 'that by which' — the means or reason linking cause to effect. Just memorize it as the fixed pair 'so / therefore.'
Example sentences
我很累，所以早点睡。
Wǒ hěn lèi, suǒyǐ zǎo diǎn shuì.
I'm tired, so I'll sleep early.
spoken
因为下雨，所以我没去公园。
Yīnwèi xiàyǔ, suǒyǐ wǒ méi qù gōngyuán.
Because it was raining, I didn't go to the park.
neutral
他喜欢中国，所以来北京学习。
Tā xǐhuan Zhōngguó, suǒyǐ lái Běijīng xuéxí.
He likes China, so he came to Beijing to study.
neutral
今天有考试，所以我要早起。
Jīntiān yǒu kǎoshì, suǒyǐ wǒ yào zǎoqǐ.
There's a test today, so I have to get up early.
spoken
所以你现在明白了吗？
Suǒyǐ nǐ xiànzài míngbai le ma?
So do you understand now?
spoken
Common phrases with 所以
Synonyms
因此 ('therefore / for this reason') is more formal and written. 所以 is the everyday spoken choice. Use 因此 in essays, news, formal speeches; 所以 in conversation.
于是 means 'thereupon / and so (then)' — emphasizes the SEQUENCE of events, not pure cause-effect. 我饿了，于是去吃饭 = 'I was hungry, so (then) I went to eat.' 所以 highlights logical conclusion; 于是 highlights what happened next.
Don't confuse 所以 with
FAQ
Acquire by listening
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