开头许下的立场，结尾要原样兑现

题目要求讨论儿童应尽早入学，还是至少七岁再入学，并给出自己的观点。开头和结尾的关系不是句型相似，而是立场一致。

一组能对上的首尾

开头：

While an early start may give children more time in formal education, I believe most should begin school at around seven, when they are better prepared for structured learning.

这句话交代双方争议，并明确选择较晚入学，理由是对结构化学习的准备度。

结尾：

In conclusion, the extra classroom time offered by an early start is less important than children's readiness to learn in a structured setting. I therefore favour beginning formal schooling at around seven.

结尾只重新衡量正文已经讨论的“课堂时间”和“准备度”，没有突然增加家庭成本或教师数量。

一组看似完整、实际没表态的首尾

In contemporary society, school starting ages have become a hot topic. This essay will discuss both views and give my opinion.

In conclusion, both views have advantages and disadvantages, and children should start school at an appropriate age.

两段都很像作文，却没有告诉读者作者认为什么。“appropriate”把最需要判断的问题藏了起来；结尾也无法回扣正文的主次。

开头可以一句、两句或更多，只要准确引入任务并让立场可辨。结尾同样不要求固定句型；把正文的关键理由重新放回同一个判断即可。写完后只需核对一件事：单独阅读开头和结尾，读者会不会得到两个不同答案。