Psychologists suggest that to cure cruelty

It's stated in the passage that

1. 
   the standard grip is the most effective way of holding the brush
   
2. 
   teeth should be brushed regularly in order to prevent the gums from receding
   
3. 
   when the bristles of a toothbrush are too soft, they can't clean the teeth effectively
   
4. 
   you'll hurt the gums of your teeth if you scrub them strongly
   

2. 
   It's advised, in the passage, that in order to obtain better results one should
   

1. 
   consult an expert for the proper way of tooth-brushing
   
2. 
   take great care of the teeth for complete well-being
   
3. 
   brush the teeth gently, moving the brush in circles
   
4. 
   not exaggerate the frequency of tooth-brushing
   

3.