PET Vocabulary II???

Complete the crossword, then click on "Check" to check your answer.
You can click on "Hint" to get a free letter but you will lose points!
 1          2    3          4   
                    
5                      
           6           
7         8               
           9           
 10                     
              11        
     12        13           
  14                    
           15          16   
  17                    
18    19                    
           20       21      
    22       23             
      24                
               25       
        26              
27                      
         28