Subjects tell the listener and the reader whom or what the sentence is about. The subject is that part of a sentence which names a person, thing, or idea. e.g. Every complete subject contains a simple subject. The simple subject, which is a noun or pronoun, is the most important word in the complete subject.
The USPS considers a postcard to be any single rectangular piece of paper that is at least 3 1/2 inches high by 5 inches long by 0.007 inch thick' and no more than 4-1/4 inches high by 6 inches long by 0.016 inches thick.. The post office considers all papers outside of these dimensions to be letters.
The size of the post card can also give a clue: 1  If the card is old and it is larger than 3.5 by 5.5 inches, it may date from before 1898. 2  If the card is old and it is slightly smaller than 3.5 by 5.5 inches, it may date from 1898 to 1902. 3  If the card measures 3.5 by 5.5 inches, it was probably made between 1902 and 1970.