Ở siêu thị gần nhà, cà phê đang giảm giá, nhưng chỉ khi bạn thanh toán bằng thẻ.

Here ở introduces the location, like at / in in English.

• Ở siêu thị gần nhà = at the supermarket near home
• Vietnamese often puts a place phrase at the beginning to set the scene.

So the sentence starts by telling you where the situation is happening.

Vietnamese often leaves possession unstated when it is obvious or not important.

• siêu thị = supermarket
• gần = near
• nhà = house / home

So siêu thị gần nhà literally looks like supermarket near home. In natural English, you usually have to choose something like near my house, near your house, or just near home.

In Vietnamese, this is normal. The exact owner of the house is often understood from context.

The comma separates the opening location phrase from the main statement.

• Ở siêu thị gần nhà, = setting the scene
• cà phê đang giảm giá = main information

This is similar to English sentences like:

• At the supermarket near my house, coffee is on sale.

The comma is not always absolutely required in every casual context, but it is very natural and helpful here.

Giảm giá means to reduce the price or to be discounted / on sale, depending on context.

With đang, it means the discount is currently happening:

• giảm giá = discounted / reduced in price
• đang giảm giá = is currently on sale / is being discounted right now

So cà phê đang giảm giá means the coffee is in a current sale period.

No, it is not strictly necessary, but it adds useful nuance.

Compare:

• Cà phê giảm giá
  = coffee is discounted / coffee gets discounted / coffee is on sale
  This can sound more general or less time-focused.

• Cà phê đang giảm giá
  = coffee is currently on sale
  This emphasizes that it is happening now.

So đang makes the sentence feel more immediate and time-specific.

Vietnamese does not use articles like a, an, or the the way English does.

So cà phê can mean:

• coffee in general
• coffee as a product
• the coffee being discussed in context

In a supermarket sentence like this, cà phê usually means coffee products or coffee in general as an item on sale.

A classifier is not needed here because the sentence is talking about the product category, not counting specific items.

Nhưng chỉ khi means but only if / but only when.

Breakdown:

• nhưng = but
• chỉ = only
• khi = when

In this sentence, chỉ khi works very much like only if in English:

• nhưng chỉ khi bạn thanh toán bằng thẻ
• but only if you pay by card

Even though khi often means when, in sentences like this the whole phrase chỉ khi expresses a condition.

Thanh toán is a more formal or standard way to say to make payment / to pay.

• thanh toán bằng thẻ = pay by card
• trả bằng thẻ = pay by card

Both can work, but thanh toán is especially common in shopping, cashier, banking, and transaction contexts.

So this sentence sounds very natural for a supermarket or advertisement.

Here bằng means by / using and shows the method or instrument.

• bằng thẻ = by card / using a card

You will also see bằng in many similar expressions:

• đi bằng xe buýt = go by bus
• viết bằng bút chì = write with a pencil
• thanh toán bằng tiền mặt = pay in cash

So bằng is a very useful word for expressing means.

Not necessarily. Thẻ just means card.

Depending on context, it could mean:

• credit card
• debit card
• bank card
• payment card in general

If Vietnamese wants to be more specific, it might say:

• thẻ tín dụng = credit card
• thẻ ghi nợ = debit card
• thẻ ngân hàng = bank card

So in this sentence, bằng thẻ usually means by card, without specifying what type.

Bạn literally means you, but in sentences like this it is often used generically, like English you in:

• You only get the discount if you pay by card.

It does not have to mean one specific person. It can address:

• the listener
• customers in general
• anyone reading the notice

So it is a very natural choice in ads, notices, and everyday explanations.

In a way, yes. Vietnamese often expresses condition-result relationships without needing every marker to appear.

The sentence is:

• cà phê đang giảm giá, nhưng chỉ khi bạn thanh toán bằng thẻ

The idea is:

• coffee is on sale, but only in the case that you pay by card

A more explicitly conditional version could be something like:

• Cà phê chỉ giảm giá khi bạn thanh toán bằng thẻ.

Or even, in other structures, Vietnamese sometimes uses nếu ... thì ... for if ... then ....

So while there is no written thì here, the conditional logic is still clear.

Yes. Vietnamese is flexible, and several versions are possible.

For example:

• Cà phê ở siêu thị gần nhà đang giảm giá, nhưng chỉ khi bạn thanh toán bằng thẻ.
• Ở siêu thị gần nhà, cà phê chỉ giảm giá khi bạn thanh toán bằng thẻ.

These are all natural, but they have slightly different focus:

• starting with Ở siêu thị gần nhà emphasizes the location first
• starting with Cà phê emphasizes the product first
• putting chỉ earlier can make the restriction feel stronger

So the original sentence is one natural way to organize the information, especially if the speaker wants to set the location first.

This is a good question because Vietnamese often does not mark this as explicitly as English does.

• giảm giá literally looks like reduce price
• but in context, cà phê đang giảm giá is understood as coffee is on sale / coffee is being discounted

Vietnamese often relies on context instead of choosing clearly between active and passive forms. In a shopping context, nobody thinks the coffee itself is doing the discounting. The intended meaning is simply that its price has been reduced.

So this expression is completely natural even though English would normally prefer a passive-like idea: coffee is discounted.

Sometimes, but the nuance changes.

• giảm giá specifically means price reduction
• khuyến mãi means promotion / special offer

A khuyến mãi might be:

• a discount
• buy one get one free
• a gift with purchase
• reward points

So if the point is specifically that the price is lower, giảm giá is better. If the store is running a broader promotion, khuyến mãi could be used instead.

They can both relate to conditions, but they are not the same.

• nếu = if
• chỉ khi = only if / only when

Compare:

• Nếu bạn thanh toán bằng thẻ, cà phê giảm giá.
  = If you pay by card, the coffee is discounted.

• Cà phê giảm giá chỉ khi bạn thanh toán bằng thẻ.
  = The coffee is discounted only if you pay by card.

The second one is more restrictive. It says card payment is the required condition.

So in your sentence, chỉ khi is important because it tells you the discount is not available otherwise.