The “Challenger Deep”, in the southern part of the Mariana Trench, at a depth of 11,000 meters(about 36,000 feet), is the deepest point of the ocean floor, world over. The Mariana Trench was formed from collision of two tectonic (构造的) plates, which were parts of the oceanic crust. One plate sank while the other climbed over, creating the deepest point of the ocean.

If Mount Everest is placed in the depths of the Mariana Trench, it would be totally submerged in water, with about 2,000 meters of water above it! The “Challenger Deep” gets its name from the British Navy vessel called “HMS Challenger” which made a first measurement of its depth in 1875.

In 1960, man reached the ultimate depth through a special underwater exploring space craft, called “Bathyscaphe”. The submersible (可下沉的) vessel called the “Trieste” reached the “Challenger Deep” on 23nd January, 1960. At that depth, the two men who were operating the submersible had about 7 miles of water over them, which exerted a pressure of 16,000 pounds per square inch! Unfortunately, they could do little except measuring the depth as their descent raised debris which reduced their visibility to zero.

Later in 1996, the Japanese unmanned remotely operated underwater vehicle (ROV), Kaiko made the deepest unmanned dive ever and brought home samples of bacteria living in these depths. The most productive dive of the “Challenger Deep” was made very recently in May 2009.The US built hybrid ROV “Nereus” reached the “Challenger Deep” and spent 10 hours on the ocean floor, sending live video data and collecting biological samples.

I personally think trains are exciting and romantic. I must admit that trains are not important means of transportation in the US, but I do have some experiences with them.

When I was a child, growing up in a small town with very little entertainment, we used to go to the station to watch the passenger trains coming in. There was something exciting about the steaming, roaring string of trains coming into view around the mountains, slowly growing larger and louder and finally after their stop crowds of strangers spilling （漏出）onto the platform.

I took my first train trip when I was ten years old. I went with my elder sister to visit our cousins six hundred miles away. The train — so loud and violent on the outside — was gentle and rocking inside. We were very excited, and as that was also our first time away from our parents, we felt somewhat frightened too. However, because I had expected so much, I was a little disappointed when I was finally one of the passengers I had watched for so long.

As a college student, I used to ride an overnight train to my roommate's hometown. We could never afford a sleeper, so we played cards, sang, ate, read and talked until we finally fell uncomfortably asleep in the straight-backed seats.

My idea that trains are romantic may come from the fact that my husband and I took the train on our honeymoon, spending extra money to eat in the dining car, and looking out of the window as the desert scenery slid past.

Now, when I make a trip, I always fly or drive, and trains are not a very important part of my life. Still, every time I hear the train whistle far away on a quiet night, I can always feel the impulse in my heart to pack my bags and jump on board, entering a unique world of motions, sounds, sights and experiences which just aren't matched in the dull environment of an airplane.

Bournemouth in Dorset has always been my favourite seaside town. When I was growing up, Mum and Dad didn’t have much money, but they’d saved enough for a few days in Bournemouth. I was four years old at the time. I don’t actually remember much about the trip, apart from being devastated when we had to leave. Mum said I fell in love with the place and insisted on waving goodbye to the sea when it was time to go. So I grew up believing Bournemouth was a wonderful place.

Forty years on, my wife and I returned for a week’s break. I was nervous, wondering if I’d be able to bring back that delight I’d felt as a child. I needn’t have worried. We had a fantastic time. It helped that the British weather had decided to provide us with high temperatures and plenty of sun. But it was Bournemouth that kept me spellbound, making me feel like a child again.

Bournemouth and its neighbour, Boscombe, are always busy, alive with chatter, music and other lively sounds. But as we stepped into Boscombe Chine Gardens, all the noise faded away. A sense of peace spread through us as we meandered along the paths, delighting in the squirrels climbing up and down the trees and the bright colours of the pretty plants.

One morning, we made a short trip to Poole Quay and took the ferry to Brownsea Island. Owned by the National Trust, it’s a feast for the eyes, from its mock Tudor entrance, to the many peacocks walking around, to the magnificent views of the sun sparkling on the shining waters and boats bobbing up and down, seen from the island’s highest point.

Before we knew it, it was time to return home—but not before waving goodbye to the sea.