下列实验操作，叙述正确的是（ ）
A．用剩的药品应放回原瓶
B．用燃着的酒精灯去点燃另一个酒精灯
C．用胶头滴管取液体时，滴管下端应紧贴试管内壁
D．加热液体时，切不可使试管对着自己或旁人
A、用剩的药品放回原瓶会污染瓶中药品，要放在指定的容器中，故A错误；
B、用燃着的酒精灯去点燃另一个酒精灯容易引发火灾，所以实验基本操作的叙述错误，故B错误；
C、用滴管滴加液体时，将滴管伸入试管中；会造成药品的污染；实验基本操作的叙述错误，故C错误；
D、加热液体时，切不可使试管对着自己或旁人，防止液体喷出伤人；实验基本操作的叙述正确，故D正确．
故选D．
Read the following passage. Complete the diagram by using the information from the passage. Write NO MORE THAN THREE WORDS for each answer. Most scientists are now certain that global warming is taking place. Gases such as carbon dioxide produced by burning of coal, oil, wood, together with industrial pollution, are creating a warm blanket around the earth. This blanket is trapping heat in the atmosphere and so raising the temperature of the earth. The evidence for global warming can now be seen in the world’s changing climate statistics. In Europe, eight of the last ten years have seen record high temperature. For northern Europe, this has generally been a change for the better. Gardens can now even grow tropical plants in England, though London may never see a “White Christmas” again. On the other hand, the countries around the Mediterranean Sea, and those south of the Sahara desert are receiving even less rain than before. In sub-Saharan Africa the crops are drying out in the fields and people are dying of starvation. In the Americans, the climate is becoming more extreme—the summers are getting hotter and the storms are becoming more violent. In 1999 the southern United States was struck by a series of destructive hurricanes, while the end of 1999 saw the worst floods ever in Venezuela. Meteorologists expect such trends to continue, and indeed to worsen, if global warming cannot be stopped. In addition to worrying about rising global temperatures and more extreme weather conditions, scientists are closely monitoring sea levels around the world. These are slowly rising, as the northern and southern polar ice-caps start to melt. This will have serious consequences for low-lying countries near the sea, such as the coral islands in the Pacific, and Bangladesh where the River Ganges already floods the delta（三角洲） every year. Already parts of these places are disappearing under the rising tides. Title: 71._______________.      
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