根据下列文章,请回答 16～22 题。 The Threat to Kiribati The people of Kiribati are afraid that one day in the not-too-distant future, their country will disappear from the face of the earth - literally. Several times this year, the Pacific island nation has been flooded by a sudden high tide. These tides, which swept across the island and destroyed houses, came when there was neither wind nor rain.'This never happened before,' say the older citizens of Kiribati. What is causing these mysterious high tides? The answer may well be global warming. When fuels like oil and coal are being burned, pollutants (污染物) are released; these pollutants trap heat in the earth's atmosphere. Warmer temperatures cause water to expand and also create more water by melting glaciers (冰川) and polar (极地的) ice caps. If the trend continues, scientists say, many countries will suffer. Bangladesh, for example, might lose one-fifth of its land. The coral (珊瑚) island nations of the Pacific, like Kiribati and the Marshall Islands, however, would face an even worse fate - they would be swallowed by the sea. The loss of these coral islands would be everyone's loss. Coral formations are home to more species than any other place on earth. The people of these nations feel frustrated. The sea, on which their economies have always been based, is suddenly threatening their existence. They don't have the money for expensive technological solutions like seawalls. And they have no control over the pollutants, which are being released mainly by activities in large industrialized countries. All they can do is to hope that industrialized countries will take steps to reduce pollution. 第 16 题 The people of Kiribati worry that one day their country will be taken away by a sudden high tide.