Learn Hardcore Chinese: kāfēiguǎn lóuxià yǒu xǐshǒujiān, shūdiàn de xǐshǒujiān zài lóushàng. - There is a restroom downstairs in the café; the bookstore’s restroom is upstairs.

Existential pattern:
[Place] + 有 + [Thing]
→ 咖啡馆楼下有洗手间
Focus: What exists in this place?
Literally: At the café downstairs, there exists a restroom.
Location pattern:
[Thing] + 在 + [Place]
→ 书店的洗手间在楼上
Focus: Where is this specific thing?
Literally: The bookstore’s restroom is located upstairs.

So:

You use 有 when you introduce the existence of something in a place.
You use 在 when you say where something (already known or specific) is.

In this sentence, the first clause is introducing that there is a restroom downstairs; the second clause is telling the location of the bookstore’s restroom. That’s why 有 is used first, and 在 is used second.

Why can you say 咖啡馆楼下 without 的, but you say 书店的洗手间 with 的?

Here 的 is used differently in the two parts.

咖啡馆楼下
This is place word + location word:
- 咖啡馆 = café
- 楼下 = downstairs (of a building / relative lower floor)
Together: 咖啡馆楼下 = downstairs from the café / the area below the café.
It is very common in Chinese to drop 的 when you have:
- a noun (place/building) +
- a location word (门口, 旁边, 对面, 楼上, 楼下, 前面, 后面, etc.)
Examples:
- 学校门口 (in front of the school)
- 图书馆对面 (opposite the library)
- 公司楼上 (upstairs from the company / in the floors above the company)
You could say 咖啡馆的楼下, but it’s longer and often unnecessary in everyday speech. Both are grammatically correct; 咖啡馆楼下 is just more natural and concise.
书店的洗手间
This is possessor + 的 + thing possessed:
- 书店 = bookstore
- 洗手间 = restroom
- 的 marks a possessive / attributive relation: the bookstore’s restroom.
Here 的 is needed to show that the restroom belongs to or is part of the bookstore. Without 的, 书店洗手间 is possible, but it sounds more like a fixed label (like a sign or category name) and is less common in simple sentences like this. 书店的洗手间 is the normal, clear form.

Could I say 在咖啡馆楼下有洗手间 instead of 咖啡馆楼下有洗手间?

You’ll most commonly hear:

咖啡馆楼下有洗手间。

The standard existential pattern is:

[Place] + 有 + [Thing]

If you add 在 before the place, you get:

在咖啡馆楼下，有洗手间。

This is not wrong, but it sounds a bit more formal or “literary” and is less common in everyday speech. In spoken Chinese, speakers usually just start straight with the place:

学校附近有超市。
公园里有很多人。
咖啡馆楼下有洗手间。

So:

在咖啡馆楼下有洗手间 is possible, but
咖啡馆楼下有洗手间 is the most natural, everyday version.

Why is the word order 咖啡馆楼下有洗手间 instead of 有洗手间在咖啡馆楼下?

Chinese and English order this type of sentence differently.

English: There is a restroom downstairs from the café.
(The “there is” often comes first.)
Natural Chinese existential pattern:
[Place] + 有 + [Thing]
→ 咖啡馆楼下有洗手间

The reversed order 有洗手间在咖啡馆楼下 is unusual and awkward in Chinese. It sounds like you’re trying to use English word order inside Chinese.

So:

Correct / natural: 咖啡馆楼下有洗手间。
Not natural: 有洗手间在咖啡馆楼下。

What exactly does 楼下 mean? Is it “under the building” or “on the floor below”?

楼下 literally comes from:

楼 = building / multi‑storey building / floor
下 = down / below

But in everyday usage, 楼下 means:

Downstairs (lower floor of the same building)
- 我住在楼上，他住在楼下。
  I live upstairs; he lives downstairs.
On a lower floor / lower level of a place
- 咖啡馆楼下有洗手间。
  There is a restroom downstairs from the café (on a lower level in that building/area).

Context decides how exactly to picture it, but it never means literally underground beneath the whole building in a physical sense like under the foundation; it’s relative to floors/levels.

Similarly, what does 楼上 mean here?

楼上 is the opposite of 楼下:

楼上 = upstairs / upper floor / the floor above

In 书店的洗手间在楼上, it means:

The restroom is on an upper floor (relative to where you are, or relative to the entrance, depending on context).

Like 楼下, 楼上 refers to higher floors in a building, not to something floating above it.

Are 楼上 and 楼下 nouns, adverbs, or what?

In practical terms for learners, treat them as location words (often called “localizers”).

In grammar terms, they function like place nouns:

They can come after 在:
- 在楼上，在楼下，在门口，在旁边
They can be the “place” part in [Place] + 有 + [Thing]:
- 楼上有一个房间。
- 咖啡馆楼下有洗手间。

So you can think of 楼上 / 楼下 as place words meaning “upper floor” / “lower floor”.

Why is there no 个 or 一 (as in 一个) before 洗手间?

In existential sentences ([Place] + 有 + [Thing]), Chinese often omits:

the number (like 一), and
the measure word (like 个),

when the exact number is not important.

So:

咖啡馆楼下有洗手间。
→ There is a restroom downstairs. (Number is not emphasized.)

If you want to emphasize the number, you can say:

咖啡馆楼下有一个洗手间。
There is one restroom downstairs.

Both are correct. The version without 一个 is more neutral and typical when you simply state that something exists there.

What’s the difference between 洗手间, 厕所, and 卫生间?

All three can refer to a toilet/restroom, but they differ slightly in tone and common usage:

洗手间 (hand‑washing room)
- Polite, softer, often used in public places, restaurants, cafés, etc.
- Very common in both Mainland China and Taiwan.
卫生间 (hygiene room)
- Also polite and neutral.
- Very common in Mainland China, often in homes and public buildings.
厕所 (toilet)
- The most direct/strong word; can sound a bit blunt depending on context.
- Still very common and not “rude”, just less euphemistic.

In a café or bookstore context, 洗手间 or 卫生间 would usually be used in signs or polite conversation; 洗手间 fits this example well.

Why is there a comma (，) instead of a period between the two clauses?

The sentence is:

咖啡馆楼下有洗手间，书店的洗手间在楼上。

This is actually two closely related clauses:

咖啡馆楼下有洗手间。
书店的洗手间在楼上。

They are being presented together as one sentence because they share a topic (restrooms in nearby places) and form a natural contrast: downstairs vs upstairs, café vs bookstore.

In Chinese writing, it is very common to join two short, related sentences with a comma:

我去买咖啡，你在这里等我。
外面下雨了，我们在家看电影吧。

You could put a period instead and have two separate sentences; the meaning would basically stay the same, but the version with a comma feels more naturally connected.