Inquiry about determiner

[ksdchan]

I would like to confirm whether my textbook answer key is correct or not.

Indicate whether the underlined determiners are definite articles, indefinite articles, demonstratives, possessives, interrogatives, relatives, or indefinites.

3. Whose shoes are those? (key: relative)
I think it should be interrogative determiner as it doesn't begin a clause.

10. China is the last nation on earth to make such trains. (key: demonstrative)
There are only four demonstrative determiners (this, that, those, these). How come 'such' is a demonstrative?

[Alan]

3. Correct: interrogative. (While frequently occurring as a relative pronoun, it is certainly not being so used here!)

10. 'Such' is not usually classified as a demonstrative, but some linguists may consider it to be one, since it implies that some person/thing is being indicated, if only as representative of a certain class or type.