句子是用来表达完整意思的词汇组合，包含主语和谓语。最基本的句子结构只包含一个分句。然而，许多句子具有一个主句和一个或多个从句。跟随澳洲代写一起来学习吧，英语句子中单词排列的标准顺序是“主语 + 动词 + 宾语”。虽然这听起来很简单，但有时主语、动词和宾语并不很容易分辨，具体取决于句子的结构和复杂程度。句子结构包括四种类型：（1）简单句，（2）并列复合句，（3）从属复合句，（4）并列-从属复合句。
句子结构类型
| 句子结构类型 | 句子的构成部分 | 示例 |
|---|---|---|
| 简单句 | 独立分句 | I like animals. |
| 并列复合句 | 独立分句 + 并列连词（或分号）+ 独立分句 | I like animals, but Molly prefers plants. |
| 从属复合句 | 独立分句 + 从属连词（或关系代词）+ 从属分句 | I like animals because they are cute. |
| 并列-从属复合句 | 独立分句 + 从属连词 + 从属从句 + 并列连词 + 独立分句 | I like animals because they are cute, so I work at an animal shelter. |
简单句的结构
简单句是最基本的句子结构形式，只由一个独立分句构成。
分句类型
一个独立分句表达一个完整的意思。只有独立分句才能作为一个完整的句子。
- Example
- The proposed system has the advantage of a wide scope.
I went shopping last weekend.
The cat is sleeping by the window.
相反，从属分句不能表达完整的意思，因此不能作为一个完整的句子存在。
- Example
- which was developed over three months
even though I was tired
because the weather is sunny
从属分句以关系代词或从属连词开头。
常见的从属连词包括
because, since, once, although, if, until, unless, why, while, whether, than, that, in order to
常见的关系代词包括
that, which, who, whom, whoever, whomever
句子的主语
主语是执行句子动作的成分。它是句子的两个基本成分（主语和谓语）中的第一个。
- Example
- This study investigated the relationship between the personal traits and clinical parameters.
- Example
- Dolly made a cake for the party.
句子的谓语
谓语包含动词（指动作），还可以包括进一步澄清的信息。
- Example
- This study investigated the relationship between the personal traits and clinical parameters.
- Example
- Mary gave her sheep a bath.
直接宾语和间接宾语
直接宾语指的是接受动作的人、物或思想等。
- Example
- This study investigated the relationship between the personal traits and clinical parameters.
- Example
- Dolly made a cake.
间接宾语指的是动作所针对的人、物或思想等对象，即动作为谁或什么而做。
- Example
- The national lab offered us an opportunity to work on an exciting new project.
- Example
- Mary gave her sheep a bath.
及物动词和不及物动词
及物动词是指主语对直接宾语所做的动作。
- Example
- We fabricated a composite.
在上例中，“we”是主语，“fabricated”是及物动词，“a composite” 是直接宾语。
不及物动词是指不需要宾语跟随的动词。不及物动词本身就可以完整地表达谓语。
- Example
- We arrived.
We arrived early.
- Example
- I always eat.
I always eat before work.
在上例中，“We”和“I”是主语。“arrived”和“eat”是不及物动词。
主语补语
主语补语通过重新命名或描述主语来补充主语的含义。主语补语总是跟在系动词后面，通常表现为英文动词“to be”的某种形式。
- Example
- The material is a gold composite.
在上例中，“gold composite”将主语“the material”重新命名或给予一个称谓。
- Example
- Charlotte is very pretty.
在上例中，“Pretty”用来描述主语“Charlotte”。
并列复合句的结构
并列复合句是由两个或两个以上的独立分句由并列连词或分号连接而成。请注意，美式英语的习惯规定，当连接独立从句时，并列连词必须与逗号一起使用。
并列复合句的结构如下: 独立分句 + 并列连词（或分号）+ 独立分句
并列连词包括: and, but, yet, or, nor, for, so
- Example
- The material is a gold composite, and it was fabricated in clean room no. 45.
- Example
- Glenda usually eats before work, but today she could not.
- Example
- The proposed system has the advantage of a wide scope; it uses a novel algorithm that expands the range by a factor of ten.
从属复合句的结构
从属复合句由一个独立分句和一个从属分句构成。
从属复合句的结构如下: 独立分句 + 从属连词 (或关系代词) + 从属分句
- Example
- We built a new system because the previous model had to be narrowed in scope.
- Example
- Sarah will buy a train ticket if her flight is cancelled.
并列-从属复合句的结构
并列-从属复合句由两个或多个独立分句和一个或多个从属分句构成。
并列-从属复合句的结构如下: 独立分句 + 从属连词 + 从属从句 + 并列连词 + 独立分
- Example
- The first method failed because it caused the wires to melt, but the second method succeeded in bending the wires without causing the same issue.
- Example
- Sarah’s flight took off before she started driving to the airport, so she drove to the train station instead.