***** NOT A TEACHER *****
Hello, Kuaile:
Thank you so much for this question. Thanks to you, I learned something new today.
In my OPINION:
(1) Yes, those two sentences are VERY different in meaning.
(2) Yes, they are both grammatically correct.
(3) I am sure that you understand The New York Times's famous motto: "All the news that's fit to print." That is to say, we promise to print ALL the news IF it is fit (that is, "proper"). The Times would print only accurate news and only news that was "respectable." No scandalous stories about famous people's private lives or advertisements for certain things that might be illegal. (Remember that the Times was founded in the 19th century when newspapers printed things that some newspapers no longer will print. So the Times promised to be a "clean" newspaper.)
(4) In my research, it seems that journalists and printers quickly started to joke about the Times's motto. They started to (jokingly) change it to "All the news that fits the print."
a. I found one explanation. I do NOT say that it is the only explanation.
b. As you know, newspapers make their money by advertisements. In fact, one famous newspaper owner defined the word "news" as the stuff that you put between the advertisements!
c. So some "wags" said that most newspapers do NOT print ALL the news that's fit (proper) to print. Those wags say that, in fact, most newspapers "print all the news that fits the print," that is to say, they print only the news for which there is AVAILABLE SPACE!
James
That particular interpretation comes from Police / The Law Enforcement Magazine (online). The editoral was entitled "Untapped Resources" by David Griffith.
Perhaps other members have different interpretations to share with us.