Nick is my good friend from England. Now let me tell you something(一些事情)about him.   

    Nick is a student and he is thirteen years old.His family are in Beijing now.His father,Mr Brown,is a manager in a hotel. His mother,Mrs Brown, is an English teachers at his school. Nick has a sister. Her name is Kate. Now they study in the same school.Look!This is a picture of their school. It is very big. There is a tall building with 23 classrooms in the middle of the school.The library is behind the tall building. The sports hall is next to the library. A playground is in front of the sports hall. It's big too. Nick and Kate like their school in Beijing very much.

①“探究酵母菌种群数量变化”的实验中，常采用五点取样法计数血球计数板中酵母菌的数量

②“观察DNA和RNA在细胞中的分布”和“观察植物细胞有丝分裂”实验中都用到HCl和酒精，它们的作用不相同．

③“观察线粒体和叶绿体”和“观察植物细胞的质壁分离和复原”实验中都必须用高倍显微镜．

④“检测生物组织中还原糖、脂肪和蛋白质”的实验中只有还原性糖的检测需要加热．

⑤用显微镜观察装片时，若用低倍镜观察可以调粗准焦螺旋，若用高倍镜观察只能调细准焦螺旋．

⑥在叶绿体色素提取实验中，可用95%乙醇中加入无水Na₂CO₃后提取色素

⑦蒸馏水在“提取纯净的动物细胞膜”和“探究生长素类似物促进插条生根的最适浓度”中的作用一致．

李大钊评论近代俄国一次重大历史事件，“今以俄人庄严璀灿之血，直接以洗涤俄国政界积年之宿秽者，间接以灌润吾国自由之胚苗”，从而使那些军阀政客、官僚耆旧们明白“专制之不可复活，民权之不可复抑，共和之不可复毁，帝政之不可复兴”。这一评论（    ）