关于地壳结构特点的正确叙述有[ ] A、大洋地壳厚度大于大陆地壳厚度 B、地壳上

句型变化。       

1. The book was written by Lu Xun. （改为主动语态)  

     Lu Xun         the book.            

2. The shoes are made by my mother. (改为否定句)    

    The shoes                       by my mother.  

3. The students wear the school clothes a lot. (改为被动语态)       

    The school clothes                     a lot by the students.            

4. The pens are used for writing words. (改为主动语态)  

    People                    for writing words.            

5.The thief caught by a policeman just now was taken into the police car. (改为同义句)  

   The thief                                by a policeman just now was taken into thepolice car.

生产经营的食品中不得添加下列哪种物质：（）

A、药品

B、既是食品又是药品的中药材

C、食品防腐剂

D、天然食用色素

恶性肿瘤通常采用组织病理学分级来表示肿瘤分化程度，（G₁～G₄）。下列陈述哪项正确（）

A.G₁低分化

B.G₁高分化

C.G₃高分化

D.G₃中分化

E.G₃未分化

将x+y中的+运算符用友元函数重载应写为　【11】　。

控制图它是用来查找问题原因的分析工具。