补全对话（共5小题，每小题2分，满分10分）

A:Hi,Ann.What are you going to do this weekend?

B: 小题1:_______________________.

A:A concert?Who will sing at the concert？

B:Swift Taylor. 小题2:_________________?

A:Sure,I’d love to.She is my favorite singer小题3:___________________?

B:Eighty yuan.

A:Oh,it’s too dear.I’m afraid 小题4:__________________________

B:We don’t have so much money,either.We plan to sell flowers to raise money.

A: 小题5:______________.Can I join you?

B:No problem.Shall we meet at the gate of the park at four oclock ?

A:Ok,See you then.

根据语境，用恰当的语言完成对话。

橡胶制品在存放过久，会产生发软；变粘的现象，使性能降低，这种现象叫做（）。