A letter of complaint should not be apologetic, but it will be found advisable for the writer to show that he regrets to make the complaint, but that the trouble is too serious to be overlooked.

• 提出异议的信件不应当是道歉性的，但写信人应对提出异议表示一定的遗憾并说明事态的严重性确实无法回避，这样做将是明智的。