1. Is there any difference between using "these" and "they"? And which
do you use more often? Which is better for these examples?
ex: What are these? –These are my clothes. / They are my clothes.
ex: I've bought some gegs. – What are
these? / What are they?
ex: Are these apples or pears? - These/
Those are pears. / They are pears?
-- I don't see much difference in many of the uses, Alex-- I suspect that
in a conversation, if deictic (demonstrative) reference is considered
necessary, these will be used, while if the indicated location is self-evident, they will be chosen-- chosen unconsciously, of course.
2. "Who are these? – These are our relatives."
This is a part of a dialog from my book. The author is not English. Is "Who are these?" not correct?
--
The sentence is correct if the context has the speaker e.g. pointing to the photograph.