yīnwèi jīntiān dǎzhé, wǒ hé tā zài chāoshì gòuwù le hěn jiǔ.

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Breakdown of yīnwèi jīntiān dǎzhé, wǒ hé tā zài chāoshì gòuwù le hěn jiǔ.

• 很hěn: very
• 和hé: and
• 她tā: she

Questions & Answers about yīnwèi jīntiān dǎzhé, wǒ hé tā zài chāoshì gòuwù le hěn jiǔ.

Why does the sentence start with 因为? Do we also need 所以 somewhere?

Chinese has a very common because–so pattern:

• 因为 A，所以 B – Because A, so B.

In your sentence we only see the 因为 part:

• 因为今天打折， 我和她在超市购物了很久。
  Because there was a sale today, she and I shopped in the supermarket for a long time.

This is completely natural. In modern Chinese you can have:

1. 因为 A，所以 B – both words used
2. 因为 A，B – only 因为 used (like your sentence)
3. A，所以 B – only 所以 used

What you cannot normally do is put 因为 in front of a clause and then not give the result:

• ✗ 因为今天打折。 (incomplete on its own)

So the sentence is fine without 所以 because the result clause 我和她在超市购物了很久 is clearly there after the comma.

In 今天打折, what is the subject? Who is actually giving the discount?

Literally, 今天打折 is “today there is a discount / sale”.
Chinese often omits the subject when it is obvious from context.

Possible fuller versions are:

• 超市今天打折。 – The supermarket has discounts today.
• 商场今天打折。 – The mall has a sale today.
• 他们今天打折。 – They are offering a discount today.

In everyday speech, when you are already talking about a store or a place, people just say:

• 今天打折
• 今天有打折

and the listener infers that “the store / this place” is doing it.

So 今天打折 is a very natural shorthand; the logical subject (the supermarket) is simply omitted.