A: This is an imperative sentence which is used in an informal way. We use this sentence structure to tell or ask people to do things (interpersonal uses) – and the question tag makes it a little bit polite.The window is closed.Two close people are talking.The speaker is not very polite.The two people are very comfortable with each other.The speaker may be annoyed.B: This type of sentence structure is used as a formal or polite request.The speaker is very polite.They are not very comfortable with each other.They could be strangers….(short extract)

+1 862 207 3288