A: I’m very tired.B: That’s because you have been working too hard.A: I know. But at least I have finished my composition.A: You look hot. What have you been doing?B: I have been playing tennis with Sarah.A: Oh yes. I have seen her play before. She's good, isn't she?B: Yes, she is. She has beaten me five times since the start of the summer.1) for2) since3) for4) since5) since6) for7) for8) for9) since10) since