Learn Hardcore Japanese: mukai no tatemono no ikkai ni tiisai mise ga arimasu. - There is a small shop on the first floor of the building across the street.

向かいの建物 means “the building opposite.”
建物の一階 means “the first floor of the building.”
Chaining them gives “the first floor of the building opposite.”

What does 向かい mean, and why can’t we say 前の建物 instead?

向かい means “across from” or “opposite.”
前の means “in front of (something).”
So 向かいの建物 is “the building across the street,” whereas 前の建物 would be “the building in front of (us or something else).”

Why is there a に after 一階 instead of another particle like で?

に marks the location where something exists.
あります is the verb for “there is/exists” (inanimate).
Thus 一階にあります = “(It) exists on the first floor.”
Using で would mark the place of an action, not simple existence.

Why do we use が before あります instead of は?

In existence sentences (あります/います), が introduces new information or the subject that exists.

小さい店があります = “There is a small shop.” (Neutral statement)
If you used は, 小さい店はあります, you’d be contrasting or emphasizing “as for the small shop, it does exist (but something else might not).”

Why is 小さい placed before 店? Can adjectives come after nouns in Japanese?

In Japanese, i-adjectives (like 小さい) always come before the noun: 小さい店 (“small shop”).
Unlike English, you cannot place an i-adjective after the noun. Some na-adjectives can post-modify with の, but that’s a different pattern.

What’s the difference between 小さい店 and 小さな店?

Both mean “small shop,” but:

小さい店 uses the i-adjective form.
小さな店 uses the na-adjective form of 小さな, which is slightly more literary or emotional.
Both are acceptable here with minimal nuance difference.

In Japanese, what does 一階 refer to—ground level or the floor above?

In Japan, 一階 is the ground floor (street level).
In some English-speaking countries (e.g., the UK), “first floor” is one level above ground—be careful with this cultural difference when translating.

Why isn’t there an explicit subject like “I” or “we” in this sentence?

Japanese often omits subjects when they’re clear from context. Here, あります (“there is”) focuses on existence. The only “subject” is 小さい店 (marked with が), and no human doer needs mentioning.