A2
因为…所以… and 虽然…但是…
Why Chinese says “because … so …” and “although … but …” where English allows only one of each, and where the connectors sit relative to the subject.
English lets you write because it rained, I didn’t go or I didn’t go because it rained — but never because it rained, so I didn’t go. Chinese does the opposite: both halves of the pair are normal, and leaving the second one out often sounds unfinished.
因为下雨，所以我没去。
Yīnwèi xià yǔ, suǒyǐ wǒ méi qù.
I didn’t go because it was raining.
虽然很贵，但是很好吃。
Suīrán hěn guì, dànshì hěn hǎochī.
It’s expensive, but it’s delicious.
虽然很贵，很好吃。
虽然很贵，但是很好吃。
虽然 sets up an expectation that something is about to cut against it, and the listener waits for the word that does. Dropping 但是 leaves the sentence hanging in a way the English translation does not suggest at all.
Either half can be dropped — but not both
In speech, one of the pair often carries the whole job, and 所以 or 但是 alone is extremely common.
下雨了，所以我没去。
Xià yǔ le, suǒyǐ wǒ méi qù.
It rained, so I didn’t go.
很贵，但是很好吃。
Hěn guì, dànshì hěn hǎochī.
Expensive, but delicious.
The asymmetry is worth noticing: dropping the first word is fine, because the second still tells you what relation the halves are in. Dropping the second is what leaves a gap.
Where the connector sits
因为 and 虽然 can go before or after the subject, and the difference is one of emphasis rather than correctness.
虽然他很忙，但是他每天都跑步。
Suīrán tā hěn máng, dànshì tā měitiān dōu pǎobù.
Although he’s busy, he runs every day.
他虽然很忙，但是每天都跑步。
Tā suīrán hěn máng, dànshì měitiān dōu pǎobù.
He’s busy, but he runs every day.
The second version names him once and then talks about him, which is usually the smoother of the two.
The rest of the family
The same both-halves shape runs through most of the connector pairs, and once you have these two the rest cost nothing:
- 不但…而且… — not only … but also
- 如果…就… — if … then
- 只要…就… — as long as … then
- 因为…才… — it is because … that
因为 pairs with 才 as well as with 所以, and the difference is the one from 就 and 才: 所以 states a consequence, 才 says this was the thing that finally made it happen.