语言学的题目,关于语言的作用,还有语言的幽默作用等,请帮我看看吧!

语言学的题目,关于语言的作用,还有语言的幽默作用等,请帮我看看吧!
Use your linguistic knowledge of sense relations to explain what makes the following humorous.
A sandwich walks into the bar and askes the bartender for a drink.The bartender says:"Sorry,we don't serve food here".
这道题哪里看出来幽默呢,我看了半天,也没找出来,
Use the sentences in the following dialogue as examples to explain the functions of language.
A.See you tomorrow.
B.Oh.I am sorry.I can't make it.
A.How come?Is everything OK?
B.Yeah,it's just that something came up at work at the last minute.I'm really sorry.
A.How does next week sound?
B.Perfect.
我觉得这里面用到了 interpersonal function,informative function,还有 emotive function 所以非常想请哪位高手帮我看看,给一个准确点的答案,