1901年梁启超在新闻报刊上有这样一段描述：“吾闻数月以来，京师及各省都会，其翻译与通事之人，身价骤增，势力极盛，于是都会人士，咸欣而慕之。昔之想科第者，今皆改而从事此途焉。”对这段材料理解准确的是

①乳酸菌、青霉菌、大肠杆菌都属于原核生物

②乳酸菌、酵母菌都含有核糖体和DNA

③T₂噬菌体的繁殖只能在宿主细胞中进行，因为它只有核糖体一种细胞器

④衣藻和蓝藻细胞中都含有叶绿体．

为社区工作的人有：____、民警、水电维修工、绿化工等。

    Memory(记忆) is very important. It helps you remember who you are, where you live, what you have learnt and what you plan to do in the future.____ 

    Memory has close relationship with the brain(大脑).____ For example, you can do new things. If you walk a different way to school or take a different bus. You will keep your brain active. You can try to remember something new. You can try to learn new skills.____ Your brain gets lost of regular exercise if you do any of these things.

    If you live a healthy life, your memory will work better. You must have a balanced diet(均衡饮食)not just fast food.____ Unless(如果不)you get enough sleep every night, you will not remember things well.

    ____ If you get too worried, your brain will slow down, and your memory will become less sharp. So, to improve your memory, you should exercise your brain, live a healthy life and stay relaxed.

阅读下面方框中的五个选项（ABCDE），从中选出可以填入空白处的最佳选项，并将其标号填在相应的横线上。