Translation from colloquial english(FOL) As homework, I had to translate the following sentence into FOL:
One can travel between any two Canadian cities by airplane, train, or bus.
P(x) - x is a Canadian city; 
Q(x, y) - one can travel by airplane between x and y;
R(x, y) - one can travel by train between x and y;
S(x, y) - one can travel by bus between x and y.
My instructors claim that the correct answer is:
∀x.∀y.P (x) ∧ P (y) → (Q(x, y) ∨ R(x, y) ∨ S(x, y))
I deny that and claim that it is :
∀x.∀y.P (x) ∧ P (y) → (Q(x, y) ∧ R(x, y) ∧ S(x, y))
My reasoning is as follows : 
I dismiss their solution by saying that it does not fully capture the information given in the given sentence. If we were in the situation that " One can travel between any two Canadian cities by airplane and not by train and not by bus. ", then the sentence given by my instructors is true and I claim that it should not since the information in the two sentences differ.
The way I reason that my solution is the correct one is that I think of Q, R and S as properties of "one". I am trying to incorporate in my solution that "one" has all of the three properties. By my instructors' solution, a case where only one of the property would be available but not  the other two would be identical with the a case where all of the properties would be available.
And one more question, from the sentence "Some students respect all professors." do we conclude that at least two students respect all professors or that we only know that at least one student respects all professors? 
 A: As you say in your title, this is a question of English, not mathematics.  I would read the sentence to say "It is possible to travel between any two Canadian cities by (at least one of) airplane, train, or bus."  In that view, using the logical connective "or" is correct.  I don't think "one" has anything to do with it.  You have clearly identified the mathematical distinction between the two readings.  
For your other question:  In mathematical English, some a is b clearly is meant to say at least one a is b, so you are only promised one.  The s on students is English, not mathematics.  If you said some student, there would be an implication that it was only one.  In a math course I would think a while before transcribing it as exactly one.
A: This is not really a question of logic, or even mathematics. It  belongs to the subfield of linguistics called semantics.  The question here, as you say, is about the meaning of the original English, and it is indeed ambiguous.
Of the many, many examples I have found so far that are construed your way, the clearest ones I have found so far have the form:

Applications must be filed by telephone, mail, or by visiting the Bursar's office.

You may console yourself by imagining how irritated your professors would be if they attempted to file by visiting the Bursar's office, and found the Bursar there sneering “the regulations say you must file by telephone, mail, or by visiting the Bursar's office.  “Or” requires at most one of these to be true in each instance, and in your case, you must file by mail, not in person.”
