I don't understand why you're able to interchange これ in 「これはペンです」and
「ペンはこれです」, but you can't interchange ここ in 「まどはここです」 and 「ここはまどです」
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2018-03-18T05:39:53.560
57349
2018-03-18T07:48:10.997
29199
question
grammar
Need help with ここ and これ
I think it's because of the topic particle. In your first sentence,「これ」 and
「ペン」refer to the same thing. While「ここ」refers to a place; the subject is「まど」.
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2018-03-18T06:49:14.210
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2018-03-18T06:49:14.210
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answer
Your assumption is not correct. In both pairs, the two sentences are **not**
interchangeable. は is called a **topic marker**. Basically, it marks what
you're talking about. Changing the topic of a sentence will usually change the
"feeling" of the sentence drastically.

これはペンです and ペンはこれです are both grammatical, but are not interchangeable. The
following two sentences are very different in meaning.

>   * これはペンです。 (This thing? This is a pen.)
>   * ペンはこれです。 (Looking for a pen? Here, this is the pen, here you go.)
>

Likewise, まどはここです and ここはまどです are both grammatical, but are not
interchangeable. The following two sentences are very different in meaning.

>   * ここはまどです。 (Curious about this structure? This is a window.)
>   * まどはここです。 (Looking for a window? Here it is.)
>
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2018-03-18T07:30:36.310
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2018-03-18T07:48:10.997
2018-03-18T07:48:10.997
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answer