问题 多项选择题

双子叶植物的根的性状特征为

A.一般为直根系

B.表面常为栓皮,较粗糙

C.形成层环大多明显

D.中心常无髓

E.自中心向外的放射状结构,木部尤为明显

答案

参考答案:A,B,C,D,E

完形填空
完形填空。
                                                                  How 3D Movies Work
     Do you know 3D movies? When you see one, it's like the story __1__ in front of you, and you are a
 part of it.  3D movies are exciting to __2__ , but do you know how __3__ them, and __4__ you need to
  wear a pair of 3D glasses? To understand these questions, let's make an easy __5__   
     Put a finger   6   your eyes.
     Cover your left eye and look at the finger.
     Cover your right eye and look at the finger.
     
     What do you see? The finger you see with your left eye is in a different position from the one you see
 with your right eye. This means you get two images (图像) when you look at __7__ with both your eyes. 
  To make a 3D movie, people have to get two images at the same time, __8__ they use two video
 cameras. When playing a 3D movie, they use two projectors (放映机) at the time.  This brings two
 images together on the screen.  Then, we use 3D glasses to separate (识别) the two images. One image
 enters one eye and __9__ enters the other eye.
    Then our brains __10__ the two images together. In this way, we get 3D pictures.
( ) 1. A. happen      
( ) 2. A. watch      
( ) 3. A.make        
( ) 4. A. when        
( ) 5. A. example    
( ) 6. A. in front of
( ) 7. A. everything  
( ) 8. A. because    
( ) 9. A. other      
( ) 10. A. let        
B. happened        
B. see              
B. to make          
B. why              
B. picture          
B. in the front of  
B. anything        
B. so              
B. the other        
B. put              
C. to happen    
C. look          
C. making        
C. which        
C. experiment    
C. behind        
C. something    
C. and          
C. others        
C. take          
D. happening      
D. notice        
D. made          
D. what          
D. movie          
D. beside        
D. nothing        
D. but            
D. the others    
D. bring          
多项选择题