补全对话。从方框中选择一个适当的句子填入空白处，使对话完整。
Mary: I called you at 7:00 last night and you didn't pick up.?
Jack: Oh, I was helping my mom in the kitchen.
Mary: I see. I called again at 8:00, and you didn't answer then either.
Jack: Oh, I know. When you called me, I was taking a shower.
Mary: But then I called again at 9:00.
Jack: Oh,
Mary: So early? That's strange.
Jack: Yeah, I was too tired.
Mary: I needed help with my homework.
