搜题请搜索小程序“爱下问搜题”
问题 填空题

用元素符号填空

（1）地壳中含量最多的金属元素______．

（2）人体中含量最高的金属元素______．

（3）金属活动性顺序表中最活泼的金属是______．

（4）目前世界年产量最高的金属元素是______．

（5）熔点最低的金属是______．

答案

（1）地壳中含量最多的金属元素是铝元素，其元素符号为：Al．

（2）人体中含量最高的金属元素是钙元素，其元素符号为：Ca．

（3）金属活动性顺序表中最活泼的金属是钾元素，其元素符号为：K．

（4）目前世界年产量最高的金属元素是铁元素，其元素符号为：Fe．

（5）熔点最低的金属是汞元素，其元素符号为：Hg．

答案为：（1）Al；（2）Ca；（3）K；4）Fe；（5）Hg．

不定项选择

仓库在商品流通中的主要职能分有（）。

A.口岸仓库

B.中转仓库

C.加工仓库（工厂）

D.存储仓库
查看答案
单项选择题

For many people today, reading is no longer relaxation. To keep up their work they must read letters, reports, trade publications, interoffice communications, not to mention newspapers and magazines: a never ending flood of words. In (1) a job or advancing in one, the ability to read and comprehend (2) can mean the difference between success and failure. Yet the unfortunate fact is that most of us are (3) readers. Most of us develop poor reading (4) at an early age, and never get over them. The main deficiency (5) in the actual stuff of language itself—words. Taken individually, words have (6) meaning until they are strung together into phrases, sentences and paragraphs. (7) , however, the untrained reader does not read groups of words. He laboriously reads one word at a time, often regressing to (8) words or passages. Regression, the tendency to look back over (9) you have just read, is a common bad habit in reading. Another habit which (10) down the speed of reading is vocalization—sounding each word either orally or mentally as (11) reads.

To overcome these bad habits, some reading clinics use a device called an (12) , which moves a bar(or curtain) down the page at a predetermined speed. The bar is set at a slightly faster rate (13) the reader finds comfortable, in order to "stretch" him. The accelerator forces the reader to read fast, (14) word by word reading, regression and subvocalization practically impossible. At first (15) is sacrificed for speed. But when you learn to read ideas and concepts, you will not only read faster, (16) your comprehension will improve. Many people have found (17) reading skill drastically improved after some training. (18) Charlie Au, a business manager, for instance. His reading rate was a reasonably good 172words a minute (19) the training; now it is an excellent 1,378 words a minute. He is delighted that how he can (20) a lot more reading material in a short period of time.

第（15）空应选择（）

A．meaning

B．comprehension

C．gist

D．regression
查看答案