不能用来鉴别蒸馏水、稀盐酸、澄清石灰水三种无色液体的是（ ）
A．pH试纸
B．碳酸钠溶液
C．紫色石蕊试液
D．稀硫酸
A、石灰水呈碱性，pH＞7；盐酸呈酸性，pH＜7；蒸馏水呈中性，pH=7，故能区分三种无色溶液；
B、石灰水能与碳酸钠反应生成碳酸钙沉淀，盐酸能与碳酸钠反应生成二氧化碳气体，碳酸钠与蒸馏水混合无现象，现象不同，故能区分三种无色溶液；
C、紫色石蕊遇到石灰水变蓝色，遇到盐酸变红色，与蒸馏水不显色，故能区分三种无色溶液；
D、稀硫酸与这三种物质混合均没有现象，所以无法鉴别；
故选：D．
Part Four: Writing Section A (10 points) Directions: Read the following passage. Complete the diagram by using the information for the passage. The art of growing dwarf （short） trees， or “bonsai” as their Japanese planters call them， is increasing in popularity in the United States. Growing bonsai can make a fascinating hobby for anyone who enjoys plants and creating beautiful effects with them. However， how can we meet the goal of making such a kind of art？ This maybe is the problem for many of us. There are， in fact， four important guidelines to follow in growing bonsai. First， one must be careful in choosing the type of tree. Not all species of trees can be made into bonsai， since the growing conditions are unusual. Second， one must be careful in choosing the size of the container the bonsai will be in. This is necessary because the major growth of bonsai is kept confined to the tree’s trunk and leaves， not its root system. Another thing the bonsai-grower must do is to trim （修整） the roots and branches of the tree periodically （定期地）。 Unless this is done， the plants will look unnatural. The Japanese ideal for bonsai is not to have the proper proportions and will have trees which are just like normal trees in everything， but in small size. The last thing one must do is to be careful to keep the miniature （small） tree well-watered， or it will die. As one can see from above， the art of bonsai-growing is one which requires a certain amount of time and effort. The satisfactions that growing bonsai brings can be great， however. Imagine having such a tree in your living room and passing it down through several generations of your family. That is exactly what bonsai-growing is all about： establishing a tradition of beauty which lasts for years and years and is a symbol of the beauties of the natural world. Title： 71. ___________
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