Input (grade 7): For example, an encyclopedia entry for Genghis Khan may begin with "Genghis Khan (c. 1162 - August 18, 1227)", suggesting that he was born in or around the year 1162.
Output (grade 6): An encyclopedia entry may begin with circa in the date of birth, for example: "Genghis Khan (c. 1162 - August 18, 1227)".