题目内容：

    On Sunday, undersea explorer Tim Taylor and his team at the Lost 52 Project announced that they had located the long-lost submarine on June 5 about 1,427 feet underwater off Okinawa, Japan. Last year, researcher Yutaka Iwasaki found that the Navy had originally made an error in translating the Japanese war records that detailed where the Grayback had likely sunk. All this time, the Navy's historical records had listed an incorrect site for the submarine's location.

With the help of autonomous underwater vehicles, remotely operated vehicles and advanced imaging technology, the team discovered the Grayback about 100 miles from the area where it was originally thought to have gone down. The discovery was officially confirmed by the Navy, Robert S. Neyland, the head of the Naval History and Heritage.

On January 28, 1944, the Grayback set sail from Pearl Harbor for the East China Sea. About a month later, the submarine reported sinking two Japanese ships on February 19. Though the Grayback was scheduled to arrive in Midway on March 7, more than three weeks passed without sight of the submarine. And on March 30, 1944, the Grayback, one of the most successful submarines of World War II, was reported lost.

Gloria Hurney, whose uncle Raymond Parks died on the Grayback, said that she wasn't sure that the Grayback would ever be recovered. So when she first learned of the discovery, she felt a mixture of shock, disbelief, sadness. Eventually, though, those feelings turned into relief, comfort and peace. Hurney said in a statement to CNN. ''I believe it will allow recovery as relatives of crew members come together to share their stories. '' Neyland said in a statement, ''Each discovery of a sunken craft is an opportunity to remember and honor the service of our Sailors. ''

1.Why was the submarine NOT found before?

A.The Navy was wrong in changing records into Japanese .

B.The technology was not so advanced.

C.No information about the submarine was obtained.

D.There was no need to find it.

2.How was the submarine located?

A.By accident. B.By the Navy's hard-working.

C.By the families' determination. D.By modern technology.

3.What can be inferred from the text?

A.People's feeling about the discovery was complicated.

B.The Grayback would be recovered soon.

C.The Grayback was the most successful submarine of the World WarⅡ.

D.The Grayback was supposed to reach the destination on April 7.

4.What is the main idea of this text?

A.Tim Taylor and his team announced a new discovery.

B.A World War Ⅱ submarine was discovered.

C.An opportunity to remember and honor the service of Sailors.

D.A mistake the Navy made in translating the Japanese war records.