I'm trying to advise am English learner of the correct word to use in the following sentence:
a I heard a story about a dog which could talk
b I heard a story about a dog who could talk
c I heard a story about a dog that could talk
Which one is correct and more importantly WHY?
Even if the dog can talk, how far do you wish to take this anthropomorphism? All the way, if you use 'who' !
That leaves the difference between 'that' and 'which', a frequent post in this forum. I will PM the clarification to you, rather than quadruplicate this in the forum. Suffice it that "that/which could talk" is a restrictive (versus non-restirctive) clause, as it defines/identifies a particular dog, as opposed to merely adding some extra information.
Restrictive clauses are introduce with 'that'
Non-restrictive are introduced with ', which"
Hence, "...about a dog that could talk."