Simple Train Platform question

[ロバート]

I'm struggling with the right word order to simply ask where the train platform is for a certain destination, but I don't think this is correct:

熊本は電車のホームをどこですか

 

[bentenmusume]

The natural way to express that would be:
熊本行き（の電車）は何番ホームですか？

Replace 何番ホーム with どこ like you originally had and you'd still probably be understood, though the former makes it clear that you're explicitly asking "which platform" (like your English example) rather than "where is the train".

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A few pointers to remember in the future:

- ～行き (read as "ゆき") is a suffix meaning "bound for". It's a very common phrase to use with trains, flights, etc.
- を is a direct object marker. When asking where X is, X is not a direct object, so ◯◯をどこですか is not grammatical. (It would be grammatical in something like, for example, この椅子をどこに置けばいいですか？"Where should I put this chair?")
- 熊本は電車～ can never mean "the train for Kumamoto", as は is a topic marking particle, and not something that can connect the words 熊本 and 電車 . If you said 熊本は電車のホームはどこですか？ (fixing the ungrammatical を), it would still be a nonsensical sentence meaning something like "Speaking of Kumamoto, where is the train platform?"

Hope this helps a bit.

 

[ロバート]

わかりました。ありがとございました。

 

[mdchachi]

I'm struggling with the right word order to simply ask where the train platform is for a certain destination, but I don't think this is correct:

熊本は電車のホームをどこですか

If it's too much to remember new patterns and confusing words like 行き right now you could easily make what you wrote correct with a few minor changes:
熊本の電車のホームはどこですか
Yes it may not be what a native would say and it may be a little ambiguous but it's a enough to get you a good helping of 日本語お上手ですね.