围绕主题句展开，支持、说明和阐述主题句的句子便是拓展句。拓展句紧扣主题句中的关键词而展开，句子与句子之间逻辑清楚，上下转承结合得当，简明扼要，重点突出。
高中英语日记范文一：
BE PATRIOTIC
要爱国
It is the duty of every citizen to make the country rich and powerful (To make the country rich and strong is...). In order to acnetplish this object one must be patriotic (love his country). I consider this an unchangeable truth.
How can a student love his country (be patriotic)? I find my answer very simple and clear. He must study hard and store up knowledge so as to serve his (the) country in the future. If every student can do according to what I said, the country will certainly be rich and powerful.
要使国家富强是每个公民的责任。为了达到此目的，必须爱国。我认为这是一条不易的定理。
一个学生如何才能爱国呢?我发觉答复很简单明了。他必须用功读书并积储知识以便将来服务国家。如果每个学生能按照我所说的去做，国家一定会富强。
高中英语日记范文二：
A TRIP TO THE COUNTRY
乡村游记
One Sunday my mother (Mother) had (made) me take my little young brother to the a trip to the country. She bade me take good care of him.
While we were walking along the road, the sun was shining brightly and the breeze was blowing gently. We saw the beautiful flowers smile (smiling) at us and heard the birds sing (singing) their sweet songs on the trees. The scenery was indeed very pretty (beautiful).
When we felt tired, we returned home. We saw Mother (our mother) wait (waiting) for us at the door.
有一个星期日，我母亲叫我带小弟弟去乡村游历。她吩咐我要好好照料他。
当我们沿着道路行走的时候，太阳灿烂地照耀着，微风轻轻地吹着。我们看见美丽的花儿对我们微笑着，并听见鸟儿在树上唱着悦耳的歌曲，风景实十分美丽。
当我们感觉到疲倦的时候，我们就回家了。我们看见母亲正在门口等候我们。
高中英语日记范文三：
BOOKS
书籍
As is well known, books teach us to learn life, truth, science and many other useful things. They increase our knowledge, broaden our minds and strengthen our character. In other words, they are our good teachers and wise friends. This is the reason why our parents always encourage us to read more books.
Reading is a good thing, but we must pay great attention to the choice of books. It is true that we can derive benefits from good books. However, bad books will do us more harm than good.
如众所周知，书籍教我们学习人生，真理，科学以及其它许多有用的东西。它们增加我们的知识，扩大我们的心胸并加强我们的品格。换句话说，它们是我们的良师益友。这是为什么我们的父母终是鼓励我们要多读书的理由。
读书是一好事，但我们必须多加注意书的选择。不错，我们能从好书中获得益处。然而，坏书却对我们有害无益。