For many years, ships that wanted to travel from the Atlantic Ocean to the Pacific or from the Pacific to the Atlantic had to sail around South America. The trip took weeks and was very dangerous.
To make the route shorter and safter, it was decided to build a canal (运河). Panama was chosen because it is the narrowest country in the Americas. The French started building the canal as early as 1880, but their attempt failed after 21,900 people died of diseases and accidents. The Americans finally completed the project, and the Panama Canal opened in 1914. When the Panama Canal opened in 1914, ships were able to make the trip between oceans in approximately 10 hours. The locks in the canal have been called one of the seven wonders of the modern world.
The 48-mile-long Panama Canal was dug through the country of Panama. To pass between oceans, ships must actually go up. In fact, to travel through the canal, ships are raised 85 feet above sea level and then lowered again.
A ship enters the canal and sails to the first series of locks. Each lock is a huge compartment(分隔的空间) made of concrete walls and metal doors at each end. When one set of doors opens, the ship enters the lock. The doors close, and water flows into the lock, raising the ship until the water level equals the level in the next lock. At that time, the doors open to allow the ship to move into the next lock. When the doors close, the same process continues to raise the ship again. On either end of the canal, three sets of locks raise and lower ships. After the third lock, the ship enters Gatun Lake, sails about 23 miles, and begins its descent through the series of locks. To lower the ship, the locks work in reverse, allowing water to flow out of the lock until the water level is the same as the next lock. In this way, the ship reaches sea level and moves out into the ocean.
Over one million ships have passed through the Panama Canal since it opened. It has proven to be very important to world trade. In 2016, the canal was expanded to allow wider ships to pass through it, proving it will be a vital part of the world for many years to come.
【小题1】Which of the following is the correct order of the events?① The ship enters a lock.
② Water flows into the lock to raise the water level.
③ The doors close.
④ The doors open and the ship move out.
| A．④③②① | B．③①②④ | C．①③②④ | D．③②④① |
| A．is the narrowest canal in the world | B．was easy to construct |
| C．is an important link in global shipping | D．will be closed in the near future |
| A．reverse | B．series | C．process | D．descent |
| A．to shorten the trip between the Atlantic and Pacific Oceans |
| B．to raise and lower the water level in the locks |
| C．so that ships could travel to Panama from other countries |
| D．so that people could enjoy the beautiful view of Gatun Lake |
