I'm sure we've done this before, but my searches returned nothing. Can anyone simplify when we should use 'that' and when we should use 'which'. i.e. My car, that I've had for many years, is in great condition. Or My car, which I've had for many years, is in great condition. Grammar Girl claims that if the sentence between commas can be removed without contextually affecting the overall sentence, we should use 'which' So, in my example the second would be correct. But I'm sure there are instances where this rule isn't relative.
My understanding is that "that" is used when the clause is essential to the sentence... so "which" would be used in your example, since you have already identified the car and you are providing additional information/ an additional clause. "One of my cars that I have owned the longest is in great condition." In this example, "that" is used because it is essential to the sentence in that it identifies which car you are referring to. Awkward sentence for illustrative purposes, a better alternative would be "the car that I have owned the longest is in great condition". But perhaps I picked up the shit end of the stick?
Thanks @Pinkymcfiddle , that makes all kinds of sense I'd wondered the same as the OP occassionally..
I agree with Pinkymcfiddle. It's worth nothing that sometimes you'll see creative writers bend the rule a bit on this issue. I've noticed a lot of writers favor "which" for an essential clause.
I believe that "that" is used to narrow... OK, I have trouble explaining it so I'll use examples: The car that is sixteen years old is in great shape. On the other hand, the car that is two years old is a mess. Here, the "that" is used to identify the car--it's this one, not the other one.
