根据对话内容，在每个标有题号的空白处填人一个适当的句子，使对话完整、合乎情景。
A: Be quick, Betty. Your uncle is waiting for you at the school gate.
B: My uncle? No, I don't have an uncle.
A: 【小题1】 ?
B: He is my grandpa.
A: Really? But he looks so young. 【小题2】 ？
B: He is 61.
A: Why is he waiting for you?
B: Today is my grandma's birthday. I will help my grandpa buy some presents for my grandma.
A: Did they buy presents for each other in the past?
B: 【小题3】 . They usually bought very special presents for each other.
A: 【小题4】 ？
B: They got married in 1976.
A: Does your grandpa still work?
B: 【小题5】 . He retired (退休) last year.(Then) Who is he?
网友回答
(答案→)(Then) Who is he?
解析：对话内容是Betty与另一同学在谈论自己的爷爷。
【小题1】根据答语，对my grandpa提问，用who。
【小题2】根据答语，对61这个年龄提问，用how old。
【小题3】根据后面的补充“They usually bought…”，可知使用肯定回答。
【小题4】根据答语，对in 1976这个时间进行提问，用when。
【小题5】根据后面一句“He retired last year.”可知，他不上班了，确定使用否定回答。