根据对话内容，在空白处填入适当的句子，使对话完整、通顺。

A: Can I help you?

B: Yes, please. .

A: Come and look at these T-shirts. They are for boys.

B: This one is nice. ?

A: 138 yuan.

B: Oh, it's expensive (昂贵的).

A: ? It's only 60 yuan.

B: Good. Well, this one is too long for my son. ?

A: Yes. Here is a short one.

B: OK, thanks.

A: .