题干

请改正下面短文中的错误。文中共有10处语言错误,每句中最多有两处。每处错误仅涉及一个单词的增加、删除或修改。

增加:在缺词处加一个漏字符号(∧),并在其下面写出该加的词;

删除:把多余的词用斜线(\)划掉;

修改:在错的词下画一横线,并在该词下面写出修改后的词。

注意:1)每处错误及其修改均仅限一词;

2)只允许修改10处,多者(从第11处起)不计分。

    Yesterday afternoon, our school held on a fire drill. We were listening the teacher carefully in the English class when we heard the fire alarm. The teacher told us to calm down and instruct us to leave a classroom in order immediately. When we got into the passage, we found they were surrounded by smoke. It was becoming difficult to breathe but to find tine way out. Finally, with our mouths covering with wet towels, we bent down and got out of the teaching building so quickly as possible. Through the fire drill I now realize what dangerous it is when there is a fire and that we should know how to escape from a fire on case of emergency.

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答案(点此获取答案解析)

①held on a 去掉on ②listening 后加to ③instruct us to 改为instructed ④leave a classroom 改为the ⑤they were surrounded 改为we ⑥but to find改为and ⑦mouths covering 改为 covered ⑧so quickly as改为 as ⑨what dangerous改为how ⑩on 改为 in

同类题1

经过实验已经证实:细胞的表面积与体积之比越大,细胞与环境之间进行物质交换的效率越高.含酚酞的琼脂遇到NaOH会呈现紫色,通过测量NaOH向 琼脂块内扩散的深度计算出NaOH扩散的体积,再根据表面积与体积的比值,来分析得出结论.请你用琼脂块模拟细胞来设计实验,验证该结论.

(1)提供的材料和试剂:塑料刀,防护手套,毫米尺,塑料勺,烧杯,吸水纸,边长为8cm的含酚酞的琼脂正方块,质量分数为0.1的NaOH溶液.

(2)方法步骤:

①用塑料刀将含酚酞的琼脂切成____ 的立方块.

②将3个琼脂块放在烧杯中,加入____ 溶液,将琼脂块淹没,用塑料勺不断搅拌.,浸泡10分钟.

③戴上手套,用塑料勺将琼脂块取出,用吸水纸将溶液吸干.

④用塑料刀将琼脂块切成两半,观察并测量NaOH扩散的溶度,作记录.

⑤将测量及计算结果填入表格

琼脂的边长(cm)

比值(表面积/体积)

NaOH扩散深度(cm)

比值(NaOH)扩散的体积/整个琼脂块体积

1

6

X

a

2

3

Y

b

3

2

Z

c

应根据什么测量出NaOH的扩散深度?测量琼脂块上____ 的厚度,预测a、b、c大小的关系为____ .

(3)分析和结论:

分析:琼脂块的体积越小,相对的表面积越____ ,物质交换越快;反之越慢.

结论:细胞越大,与环境进行物质交换的效率越____ .因此,生物体器官的大小取决于细胞的____ .通过以上实验可以说明,细胞的体积____ ,因为细胞过大,与环境进行物质交换效率低,不能保证细胞生命活动和能量的需求.