1.First published in 1927, the charts remain an _______ source for researchers.
  A intelligent 
  B indispensable
   C inevitable 
  D identical 
  
2. Please___ dictionaries when you are not sure of____ word spelling or meaning.
  A search 
  B seek 
  C inquire 
  D consult
  
3. It ____ you to at least 50% off the regular price of either frames or lenses when you buy both.  
  A credits 
  B entitles 
  C presents 
  D tips
  
4. The __ at the military academy is so rigid that students can hardly bear it.
  A confinement 
  B convention 
  C discipline 
  D principle
  
5. Doctors warned agaisnt chewing tobacco as a _____ for smoking.
  A succession 
  B substitute 
  C revival 
  D relief