Verbs stating that something exists at a location, or that you have something. います (いる) is for animate beings (people, animals). あります (ある) is for inanimate objects and abstract things.
[Place] に [Noun] が います/あります
公園に子供がいます。
Kouen ni kodomo ga imasu.
There are children in the park.
子供 (child = animate) が います
机の上に本があります。
Tsukue no ue ni hon ga arimasu.
There is a book on the desk.
本 (book = inanimate) が あります
時間があります。
Jikan ga arimasu.
I have time.
abstract thing (time) 'exists' for me = 'I have time'
• The Animacy Test: Does it move under its own will? Yes → いる (people, animals, insects). No → ある (books, plants, things). Cars and robots are treated as inanimate → ある. • Event Occurrences: あります also declares that an event will take place: 明日パーティーがあります (there's a party tomorrow); 試験がある (there's a test). • Core Particles: Existence pairs with に (location) and が (the thing that exists).
The JLPT rarely asks whether you recognise a pattern — it asks which of several similar patterns fits. These are the ones いる is tested against.
いる/ある state physical existence or possession ('there is', 'I have'); です/だ equate identity ('A is B'). '本があります' = there is a book vs '本です' = it is a book.
ある can mean 'have' for things at hand or abstract (時間がある, お金がある); 持っている stresses actively owning/holding a concrete possession (車を持っている = I own a car).
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