将下列句子变成相对应的语态。

1. Farmers grow rice in the field.

                     by farmers in the field.

2. This sad novel was written by Charles Dickens.  

Charles Dickens         this sad novel.      

3. The exciting movie was directed by Zhang Yi-mou.    

Zhang Yimou          the exciting movie.

4. Yesterday he cut the old tree.  

The old tree                  by him yesterday.

5. My parents ask me to watch only the TV news.  

                          to watch only the TV news.

下图示神经元局部模式图。当人体内兴奋流经该神经元时，在神经纤维膜内外的电流方向是（）

A.都是由左向右

B.都是由右向左

C.膜内由左向右，膜外由右向左

D.膜内由右向左，膜外由左向右