Breakdown of tomodati to kuzi ni yakusoku ga arimasu.
友達tomodati
friend
とto
companion particle
がga
subject particle
にni
time particle
あるaru
to have
九時kuzi
nine o'clock
約束yakusoku
appointment
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Questions & Answers about tomodati to kuzi ni yakusoku ga arimasu.
Why is the subject omitted in this sentence? How do we know who has the appointment?
Japanese often drops the subject when it’s clear from context. Here, because you’re talking about your own schedule, it’s understood that I (the speaker) have the appointment. If you needed to clarify, you could say 私は友達と九時に約束があります.
What does と indicate in 友達と?
The particle と here means “together with” or “with.” It connects 友達 (friend) to the action or event, indicating you have an arrangement with a friend.
Why is に used after 九時?
に marks a specific point in time. When you want to say “at nine o’clock,” you attach に to 九時. Without に, the time wouldn’t be properly specified as the moment the appointment occurs.
Why is が used before あります?
In the pattern X が あります, が marks X as the subject (or the thing that exists). Here, 約束 is the thing that “exists” or is in your schedule. So 約束がある literally means “an appointment exists.”
Could we replace が with は in 約束が?
Yes, you could say 約束はあります, but that turns 約束 into the topic rather than the new information. Using が presents the fact “I have an appointment” as fresh info. Using は might imply contrast, like “As for appointments, I (do) have one,” perhaps in response to “Do you have any appointments?”
Why is あります used instead of います?
ある/あります is used for things or events inanimate in Japanese grammar. Even though appointments involve people, the word 約束 itself is treated as an inanimate “thing,” so you use あります.
What does 約束 mean here? Doesn’t it also mean “promise”?
Yes, 約束 can mean “promise,” but in this context it means “appointment,” “arrangement,” or “plan (to meet).” If you wanted to emphasize that you “promise” someone something, you’d usually specify the content.
Why doesn’t the sentence say 会う? How do we know the promise is to meet?
In Japanese, 友達と約束があります by default implies you’ll meet your friend. If you want to be explicit, you can insert the verb: 友達と会う約束があります (“I have an arrangement to meet with a friend”).
Can we change the word order?
Yes. Japanese word order is relatively flexible. For example you can say 九時に友達と約束があります or 約束が九時に友達とあります (latter is unusual but still understandable). The particles keep each element’s function clear.