Fragmentary waterclock (klepsydra). The ΧΧ stands for two χόες, about 6.4 liters, which takes about six minutes to run out. Late 5th c. B.C. Athenian Agora Excavations. Key Terms and Concepts: FIRST PERSON PRONOUN SECOND PERSON PRONOUN REFLEXIVE FIRST PERSON PRONOUN REFLEXIVE SECOND PERSON PRONOUN REFLEXIVE THIRD PERSON PRONOUN RECIPROCAL PRONOUN Chapter Navigation Key Terms and Concepts Pronouns Review First Person Pronoun Second Person Pronoun Reflexive Pronouns Reciprocal Pronoun Exercises 26 Book Nav Exercises 25 Review: Pronouns