| A | B | 
| bulkhead | a framework with a sloping door giving access to a cellar | 
| demeanor | an expression or reaction | 
| invincible | not able to be beaten or defeated | 
| limitation | the state of being limited | 
| ornithopter | an experimental device propelled by flapping wings (a mechanical bird) | 
| sobriquet | a nickname | 
| alternative | other | 
| compass | a device that uses magnetism to aim a needle north | 
| megaphone | a cone-shaped device used to increase teh sound of a voice | 
| perspective | point of view | 
| clause | a group of words that contain a subject and a verb | 
| depedent clause | group of wors that does not express a complete thought and cannot stand alone as a sentence | 
| independent clause | group of words that does express a complete thought and can stand alone as a sentence | 
| simple sentence | contains 1 independent clause and no dependent clauses | 
| compound sentence | contains 2 or more independent clauses and no dependent clauses | 
| complex sentence | contains 1 independent clause and 1 or more dependent clauses | 
| compound-complex sentence | contains 2 or more independent clauses and 1 or more dependent clauses | 
| vacant | not occupied or empty | 
| fiend | evil spirit or demon |