题干

古今中外所有成就事业的人,在前进的道路上,不就是靠着这种“滴水穿石”的精神,才“滴穿”一块块“顽石”,最终取得成功的吗?

语段中“滴水穿石”加双引号,作用是:


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同类题2

完形填空

    先通读下面的短文,掌握其大意,然后在每小题所给的A、B、C、D四个选项中,选出可以填入空白处的最佳选项。

    Creativity(创造力)is the key to a bright future. Here is 1 schools and parents can help their children to develop their creativity.

    Drew worked for a company in 1925. At work he invented(发明)a kind of material 2 enough to hold things together. But his boss told him not to think more about the idea. Drew didn't stop and finally, using his own time, made a kind of tape, which now is used everywhere by many people. And his company learned from its 3 .Now the company asked its workers to 4 15 percent of their work time just thinking about and developing new ideas.

    Creativity is not something one is just born with. A person with high intelligence(智力)does not mean that he uses it creatively. Creativity is the matter of 5 your intelligence to think of new ideas that are good for something.

    We know that many schools have tried to develop students' creativity, but some teachers only want to develop students' reading, writing and math skills, and have to 6creativity for correct answers. Children from such schools can give correct answers, but they are unable to use 7 to work out problems.

    It is important to give children choices. From the earliest age, children should learn to make decisions and understand their 8. Even though it's choosing between two kinds of food 9 lunch, decision-making helps thinking skills. As children grow older, parents should let their children decide how to use their time or spend their money, but not help them too much if they make the wrong decision. The child may have a 10 time, but that is all right.

同类题5

某同学想研究氨基酸的分离和鉴定的方法,已知实验室中有0.5%的赖氨酸、脯氨酸、缬氨酸、苯丙氨酸、亮氨酸溶液以及它们的混合液(各组份浓度均为0.5% );A.器材:层析缸、毛细吸管、喷雾器、滤纸、其他相关器材( 剪刀、铅笔、透明胶带等);B.试剂:层析液(4份水饱和的正丁醇和1份醋酸的混合物)、0.1%茚三酮溶液.若该同学想证明混合液确实含有上述 5 种氨基酸,请利用题目所给条件设计试验:

(1)实验原理:

①所有氨基酸和一切蛋白质都能和茚三酮发生颜色反应

②在一定条件下,不同的氨基酸在层析液中的____ 不同,所以在滤纸上的扩散速度不同,从而出现在滤纸的不同位置上

(2)实验步骤:

①取层析滤纸一张,剪成20厘米长、14 厘米宽的滤纸条,在纸的一端距边缘 2~3 厘米处用铅笔画一条直线,在此直线上每间隔2厘米作一记号,共需作____ 处记号;

②用____ 吸取氨基酸样品点在标记上,干燥后重复2﹣3次.

③将处理好的滤纸条卷成筒状用透明胶带固定,放入加好了层析液的层析缸中,待层析液上升到一定阶段时取出滤纸,自然风干;本步骤需要注意的是:点样的一端在下; 层析液的液面要____ ( 填“高于”或“低于”)点样线.

④用喷雾器向滤纸上均匀喷上____ ,待干燥后观察并记录层析斑点的位置.

(3)已知5种氨基酸的扩散速度为:赖氨酸<脯氨酸<缬氨酸<苯丙氨酸<亮氨酸.如图为实验结果,不同氨基酸用1~5表示,请问图中标号为1的氨基酸是____ .