Diving Some people enjoy deep-sea diving as a sport. But for most divers it is a way of teaching jobs that must be done under water. For example, deep-sea divers raise sunken ships. They help build underwater foundations for bridges and piers. Sometimes, divers recover great treasures of gold and silver and other valuable cargoes from the holds of sunken ships. A diver faces danger each time he goes under water. His life depends on a steady supply of air pumped to him through a hose from the surface. He usually wears a bulky waterproof suit and a metal helmet that make it difficult to move about. Often a diver must feel his way through icy water filled with mud and silt that make it hard to see. If a diver rises to the surface too rapidly, he may suffer a sickness called the bends. There are four main kinds of deep-sea divers. Commercial divers salvage sunken ships, cargoes, and aircraft, and help build or repair docks, breakwater, bridges etc. Open-sea divers harvest some products of the sea. Research divers search the bottoms of oceans for oil and conduct scientific investigations of sea life, etc. Military divers blow up harbor defenses, clear mines from harbors, and also salvage sunken ships and aircraft. 1. The air a deep-sea diver breaths is supplied by . A) people ashore or in a boat above B) automatic engine in his hand C) it storage in his metal helmet D) its storage inside his waterproof suit 2. Which of the following titles gives the best description of the passage? A) The modern Knight in Armor B) Diving for Fun C) Diving for Sunken Ships D) Deep-Sea Diving 3. When petroleum is used up, what kind of diver will be busier? A) Open-sea. B) Military. C) Research. D) Commercial. 4. A sea life raiser could be a . A) research diver B) commercial diver C) open-sea diver D) military diver 5. The word "bends" (in Para. 2) is probably . A) an action B) a pump C) an air supplier D) a disease