sore: in this context, "sore" refers to pain or discomfort in rachel's foot. she might be experiencing physical pain or tenderness.
actually: rachel uses "actually" to provide additional information or correct mary's assumption. in this case, she clarifies that the sport is not tennis or basketball but rather a volleyball tournament.
tournament: a tournament is a competition in which participants compete against each other, often in a series of matches, to determine a winner. in this dialogue, it refers to a volleyball competition at the sports center.
that's so cool!: this is an expression of excitement and approval. mary is enthusiastic about the idea of a volleyball tournament and expresses it by saying, "that's so cool!"
you bet!: this is an informal way of saying "definitely" or "certainly." mary is expressing strong agreement and eagerness to play volleyball with the team.
pal: "pal" is a friendly and informal term used to address a friend or acquaintance. in this case, rachel uses it to thank mary for agreeing to take her place in the volleyball match.