Question

1. Do you remember the day when we met first?

1-1. Do you remember when we met first?

2. Do you remember the day on which when we dmet first?

(Can we use #1-1?)


3. Tell me the reason why you were late.
4. Tell me why you were late.
(We can delete 'the reason' in Sentence 3. Then we get #4. In #4, what is the part of speech of 'why'? In #3, 'why' was a relative adverb.' In #4, is 'why' a relative adverb or 'an interrogative adverb'?)

5. This is the reason why you were late.
6. This is why you were late.
(In #5, 'why' is a relative adverb. In #6, is 'why' a relative adverb or an interrogative adverb?)

Answer 1

1. Do you remember the day when we <b>first met</b>? <~~Word order matters!

1-1. Do you remember when we met first? <b>not OK</b>

2. Do you remember the day on which when we met first? <b>not OK</b>

<b>Any of these can be used correctly if you put "first" before "met."</b>
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3. Tell me the reason why you were late.
4. Tell me why you were late.
(We can delete 'the reason' in Sentence 3. Then we get #4. <b>Yes. You can use either 3 or 4, but the redundancy makes 4 the better phrasing.</b>

<b>In 4 and 6, "why" is an interrogative adverb that is used to introduce the indirect question. I wouldn't use 3 or 5 because of the redundancy.</b>