题目

下列说法错误的是（） A . 陶瓷是以黏土为主要原料，经高温烧结而成 B . 普通玻璃以纯碱、石灰和石英砂为原料，发生复杂的物理和化学变化制得 C . 普通硅酸盐水泥以黏土和石灰石为主要原料 D . 向水泥中加入适量的石膏可以调节水泥硬化速率 答案：B阅读下面短文，用文中括号内所给动词填空。     Since 1946, one of the most important inventions has been the computer. It has been changing all our lives.     The first computer   _1   _ (build) in 1946.It    2     (be) as large as a room and quite difficult and slow     3     ( use). But since the invention of silicon " chip " (硅片) ,  computers      4     ( become)  smaller,  easier and faster to operate. Some computers are as small as TV sets. Some can even      5     (make) smaller than a book. And computers      6    ( get) smaller and smaller all the time. Who knows what the computers of tomorrow     7    (be) like?     There      8     (be)  several reasons why the computer is useful to us. First,  a lot of information can be put into computers. Second, the computer _   9     (work) very quickly thousands of times faster than a man and it will not be tired. Third, modern computers can be built into other kinds of machines, like radios, cars and planes. So today people can spend less time     10    ( do) more work with a computer.1.______ 2. _______3. _______4. _______ 5. ______6. ______7. _______8. _______9. _______10. ______