As a physician who travels quite a lot, I spend a lot of time on planes listening for that dreaded “Is there a doctor on board?” announcement. I’ve been   16  only once — for a woman who had merely fainted. But the   17  made me quite curious about how   18  this kind of thing happens. I wondered what I would do if   19  with a real midair medical emergency — without access   20  a hospital staff and the usual emergency equipment. So   21  the New England Journal of Medicine last week   22  a study about in-flight medical events, I read it   23  interest.
　　The study estimated that there are a(n)   24  of 30 in-flight medical emergencies on U.S. flights every day. Most of them are not   25 ; fainting and dizziness are the most frequent complaints.  26  13% of them — roughly four a day — are serious enough to   27  a pilot to change course. The most common of the serious emergencies   28  heart trouble, strokes, and difficulty breathing.
　　Let’s face it: plane rides are   29 . For starters, cabin pressures at high altitudes are set at roughly      30  they would be if you lived at 5,000 to 8,000 feet above sea level. Most people can tolerate these pressures pretty   31 , but passengers with heart disease   32  experience chest pains as a result of the reduced amount of oxygen flowing through their blood.   33  common in-flight problem is deep venous thrombosis — the so-called economy class syndrome (综合症).   34  happens, don’t panic. Things are getting better on the in-flight-emergency front. Thanks to more recent legislation (立法), flights with at      35  one attendant are starting to install emergency medical kits to treat heart attacks.

　 You may think that sailing is difficult, but it is really not hard to learn it. You do not need to be strong. But you need to be quick. And you need to understand a few basic rules about the wind.

　 First, you must ask yourself, “Where is the wind coming from? Is it coming from ahead or behind or from the side?” You must think about this all the time on the boat. The wind direction tells you what to do with the sail(帆).

　 Let’s start with the wind blowing from behind. This means the wind and the boat are going in the same direction. Then you must always keep the sail outside the boat. It should be at a 90° angle (角度) to the boat. Then it will catch the wind best.

　 If the wind is blowing from the side, it is blowing across the boat. In this case, you must keep the sail half way outside the boat. It should be at a 45° angle to the boat. It needs to be out far enough to catch the wind. but it shouldn’t flap (摆动). It shouldn’t look like a flag on a flagpole. If it is flapping, it is probably out too far, and the boat will slow down.

　 Sailing into the wind is not possible. If you try, the sail will flap and the boat will stop. You may want to go in that direction. It is possible, but you can’t go in a straight line. You must go first in one direction and then in another. This is called tacking. When you are tacking, you must always keep the sail inside the boat.

64. What should you consider first while sailing?

　 A. Sailors’ strength.

　 B. Wave levels.

　 C. Wind directions.

　 D. Size of sails.

65. What does the word “It” underlined in Paragraph 4 refer to?

　 A. The sail.

　 B. The wind.

　 C. The boat.

　 D. The angle.

66. What do you have to do when sailing against the wind?

　 A. Move in a straight line.

　 B. Allow the sail to flap.

　 C. Lower the sail.

　 D. Tack the boat.

As a physician who travels quite a lot, I spend a lot of time on planes listening for that dreaded “Is there a doctor on board?” announcement. I’ve been   16  only once — for a woman who had merely fainted. But the   17  made me quite curious about how   18  this kind of thing happens. I wondered what I would do if   19  with a real midair medical emergency — without access   20  a hospital staff and the usual emergency equipment. So   21  the New England Journal of Medicine last week   22  a study about in-flight medical events, I read it   23  interest.

　　The study estimated that there are a(n)   24  of 30 in-flight medical emergencies on U.S. flights every day. Most of them are not   25 ; fainting and dizziness are the most frequent complaints.  26  13% of them — roughly four a day — are serious enough to   27  a pilot to change course. The most common of the serious emergencies   28  heart trouble, strokes, and difficulty breathing.

　　Let’s face it: plane rides are   29 . For starters, cabin pressures at high altitudes are set at roughly      30  they would be if you lived at 5,000 to 8,000 feet above sea level. Most people can tolerate these pressures pretty   31 , but passengers with heart disease   32  experience chest pains as a result of the reduced amount of oxygen flowing through their blood.   33  common in-flight problem is deep venous thrombosis — the so-called economy class syndrome (综合症).   34  happens, don’t panic. Things are getting better on the in-flight-emergency front. Thanks to more recent legislation (立法), flights with at      35  one attendant are starting to install emergency medical kits to treat heart attacks.