问题 解答题

以下是制作临时装片步骤的主要步骤:

①在载玻片中央滴一滴清水    ②用镊子撕取实验材料     ③用染液给实验材料染色    ④盖上盖玻片    ⑤擦拭载、盖玻片  

⑥将实验材料浸入载玻片上的水滴中并展平.

请你按这些步骤的先后顺序排序(只填写序号)______.

答案

擦:用干净的纱布把载玻片和盖玻片擦拭干净;

滴:把载玻片放在实验台上,用滴管在载玻片的中央滴一滴清水;

撕:用镊子撕取实验材料中薄的一片;

展:把撕取的薄膜放在载玻片中央的水滴中,用解剖针轻轻的把水滴中的薄膜展平;

盖:用镊子夹起盖玻片,使它的一端先接触载玻片上的液滴,然后缓缓放平;

染:在盖玻片的一侧滴加碘液,另一侧用吸水纸吸引,重复2~3次,使染液浸润到标本的全部.

故答案为:⑤①②⑥④③

阅读理解

阅读理解

     Let children learn to judge their own work. A child learning to talk does not learn by being corrected

all the time; if corrected too much, he will stop talking. He notices a thousand times a day the difference

between the language he uses and the language those around him use. Bit by bit, he makes the necessary

changes to make his language like other people's. In the same way, children learn to do all the other things without being taught to walk, run, climb, whistle, ride a bicycle…They compare their own performances

with those of more skilled people, and slowly make the needed changes. But in school we never give a |

child a chance to find out his mistakes and correct them for himself. We do it all for him. We act as if we

thought that he would never notice a mistake. If it is a matter in mathematics or science, give him the

answer book. Let him correct his own papers. Why should we teachers waste time in such routine(日常的)work? Our job should be to help the child when he tells us that he can't find the way to get the right

answer. Let the children learn what all educated persons must some day learn, how to measure their own

understanding, how to know what he does not know.

1. According to the passage, the best way for children to learn things is by_____.

A. listening to skilled people's advice.

B. asking older people many questions

C. making mistakes and having them corrected

D. doing what other people do

2. Which of the following does the writer think teachers should NOT do?

A. Give children correct answers

B. Allow children to mark mistakes.

C. Point out children's mistakes to them.

D. Let children mark their own work

3. According to the writer, teachers in school should _____

A. allow children to learn from each other

B. point out children's mistakes whenever found

C. correct children's mistakes as soon as possible

D. give children more book knowledge

4. The passage suggests that learning to speak and learning to ride a bicycle are____

A. different from learning other skills

B. the same as learning skills

C. more important than other skills

D. not really important skills

单项选择题