Question

1. Do you know the zip code for Dokdo?

2. Do you know what the zip code for Dokdo is?

3. Do you knwo what is the zip code for Dokdo?

4. What is the zip code for Dokdo?

(Which questions are correct?)

Answer 1

All are correct, but obviously 4 is the best.

Answer 2

There are errors in #3. Do you see them?

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