19、I once experienced an unforgettable trip to Gloucester to see some of the world's most beautiful and exciting animals in their own habitat（棲息地）, the North Atlantic Ocean.

    After a long trip by bus, we got on the ship. After a while, we stopped and everyone on the ship started to shout because we saw a humpback whale（座頭鯨）. It was wonderful. Sometimes, whales came so close to the ship that you thought you could easily touch them.

    While we were watching the whales, a guide was giving us some information about them. She told us that we saw only two kinds of whales -- 50-foot humpback whales （singing whales） and 70-foot fin back whales （the second largest whales on earth）. She also said we could easily recognize a whale by its tail because every whale has a different kind of tail just like people have different fingerprints.

    They all have names, and on this trip, we saw "Salt" and "Pepper", two whales named by a biologist and a fisherman. They were swimming together all the time.

    I took twenty-seven photos, but it was very hard to take them because the whales were quick and stayed on the surface（表面） of the ocean just for a short time. It was really something. It was one of the chances that a person hardly ever experiences in life, but I had that chance.

1. This passage is mainly about ____.

    A. an unforgettable experience in the forest

    B. an unforgettable trip to see some strange animals in the mountains

    C. a long trip on the ship

    D. an unforgettable trip to watch whales

2. Everyone on the ship began to shout because ______.

    A. a whale came so close to the ship                  B. they saw a singing whale

C. they saw a fin back whale                             D. they could touch the whale

3. When they were watching the whales, ____.

A. some of them fed the whales

B. they found several kinds of whales

C. a guide told them something about the whales

D. some of them took many photos and touched the whales

4. How can we recognize a whale?

A. By its tail（認(rèn)識）.                            B. By its head.

C. By its neck.                                      D. By its eyes.