根据上下文，补全对话中所缺的单词，每空一词。

A: Can I help you?

B: Yes, please. Today is Mother's Day. I want to buy a present for my 1.           . But I don't know what

    to buy.

A: Maybe you can buy her some 2.           .

B: Great! But what flowers should I buy?

A: I think carnations are better. They show happiness and love. They are for mothers.

B: How 3.            are they?

A: Twenty yuan a bunch (束).

B: OK. I'll buy carnations. Here is the 4.           .

A: Thank you and best 5.            to your mother.