
Retired English Teacher
Hello.
Is there any difference?
(A) Visiting relatives can be boring.
(B) Visiting relatives could be boring.
Out of curiosity, by "visiting relatives", do you mean relatives who are visiting you, or the act of you going to visit relatives?
Yes.
Setting aside the alternative semantic interpretation ("relatives who visit can be boring"),
the first would mean
It is sometimes boring to visit relatives.
while the second either
It might be boring to visit relatives.
(i.e. if we ever actually did so).
or
It was sometimes boring to visit relatives.
(i.e. when we did it in the past).
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