Question: is pencil a proper noun?
Answer: Rules of Using Common Nouns A common noun does not start with a capital letter. For example: 'a car' and not 'a Car' or, 'a pencil' not 'a Pencil'. A common noun can only be capitalized if it is associated with a name in the sentence that is 'Aunt Katherine' not 'aunt Katherine' or 'Sir Nicholas' not 'sir Nicholas'.