***** NOT A TEACHER
*****
Hello, Batman:
After checking my books, consulting the Web, and reading Lotus's post (which, I notice, she has deleted), I now have a
little more confidence that my ideas (not "answers") are reasonably accurate.
I now believe that you are correct
and incorrect.
*****
You are correct in saying that the
general rule in English is: if the first verb is past, then make the second verb past.
a. Thus, "I
thought that out-of-towners
went back to their hometowns during holidays" would probably be accepted as correct on a test by many teachers. And some people actually expect it in formal writing.
BUT -- as you can imagine -- there is a
big exception.
My first source states it beautifully:
"If the statement in the dependent clause ["that out-of-towners ___ back to their hometowns during holidays"] is unvaringly true [the information NEVER changes], the present tense should
naturally be retained."
So -- as Lotus taught us -- it would be very, very correct to say "I
thought that out-of-towners
go back to their hometowns during holidays" because it is "unvaringly true" that during holidays, they ALWAYS go home.
*****
My second source gives us some wonderful examples of how native speakers break the rule:
a. He ASKED the guard what time the train usually STARTS. [It always startS at that time.]
b. He TOLD me that Mary IS quite diligent. [She IS a diligent girl. That is a permanent characteristic.]
c. He DIDn't know that nettles STING. [I don't know what "nettles" are, but apparently stinging is a permanent characteristic.]
d. Columbus PROVED that the world IS round. [My books tell me that ALL teachers like "d." You know that the world is always going to stay round. As far as "a" - "c" are concerned, there are some people who would NOT break the rule. But if you do break the rule (as has been done in "a" - "c"), they are considered fine and many books actually prefer and recommend breaking the rule in such cases.]
James
First source: Eric M. Steel,
Readable Writing (1950). I found it in the "books" section of Google.
Second source: George O. Curme,
A Grammar of the English Language (1931). Yes, 1931 was many years ago, but I have NO doubt that his examples are as relevant in 2014 as they were in 1931.