很多学生在写作时，由于语法基础薄弱，导致写出来的句子的语法错误非常多。而语法在托福写作中是基石，准确的语法能够帮助学生快速提分。本次总结了学生写作中出现的三大类常见错误，希望学生通过改错练习达成两个目的，一是加强语法知识，二是形成写作检查的意识，减少类似写作的语法错误。
在英语中，在句子中连接思想和建立各种关系的主要操作符如下:1.介词（The prepositions）2.连词（The conjunctions）3.连接副词（The conjunctive adverbs）。
名词相关的错误
---可数名词单独出现
--- 滥用the
--- 不可数名词加s
--- a/an使用不对
1. they need to learn various knowledges and know lots of people in different fields.
错误原因：不可数名词加s
改正：they need to learn various knowledge and know lots of people in different fields.
2.Technological equipments are commonly used in class, making a lecture more engaging.
错误原因：不可数名词加s
改正：Technological equipment are commonly used in class, making a lecture more engaging.
3. The indoor activities will not be affected by weather changes. If the weather is sunny and hot, the indoor places with air-conditioners must be a best choice.
错误原因：滥用the
改正：Indoor activities will not be affected by weather changes. If the weather is sunny and hot, indoor places with air-conditioners must be a best choice.
4. Companionship is one of the benefit raising a pet can generate.
错误原因：名词单复数错误
改正：Companionship is one of the benefits raising a pet can generate.
5. A honest leader always think the most important thing is to make sure the benefits of organizations and schools.
错误原因：a/an使用错误
改正：An honest leader always think the most important thing is to make sure the benefits of organizations and schools.
6.Therefore, they had to ask their parents to make a decision for them quickly or seek others’ advises in about three weeks.
错误原因：不可数名词加s
改正：Therefore, they had to ask their parents to make a decision for them quickly or seek others’ advice in about three weeks.
动词相关的错误
--- 遗漏be动词
--- 多谓语动词错误，缺少合适语法进行连接
--- 动词形式不对（三单，现在分词，过去分词，不定式）
1. they will do prepare for the next classes in order to let students understand the knowledge better.
错误原因： 多谓语动词错误
改正：they will prepare for the next classes in order to let students understand the knowledge better.
2.The reading propose three methods to control cane toads were introduced to Australia in 1935 and threated the native animals.
错误原因： 三单错误，多谓语动词错误
改正：The reading proposes three methods to control cane toads that were introduced to Australia in 1935 and threated the native animals.
3.No matter where the fence located, these waterways carry the young toads and eggs to the other side.
错误原因： 缺少be动词
改正：No matter where the fence is located。
4. There is a number of companies which performs poorly in obeying environment protection rules and regulations
错误原因： 主谓不一致
改正：There is a number of companies which perform poorly in obeying environment protection rules and regulations。
5. The public would able to have a better understanding and comply with rules
错误原因： 缺少be动词
改正：The public would be able to have a better understanding and comply with rules.
6.Raise a pet can help children learn the sense of responsibility.
错误原因： 动词原词做主语
改正：Raising a pet can help children learn the sense of responsibility.
从句相关的错误
--- 引导词使用错误
--- 句子结构不对
--- 标点符号错误
--- 从句使用不当，导致缺少主句
1.they may have felt discouraged and desperate because the huge amount of medical costs that they cannot afford.
错误原因：because后面缺少从句的结构
改正：they may have felt discouraged and desperate because they cannot afford the huge amount of medical costs.
2. when a politician wants to investigate poverty problems in a city, then learn about their daily life’s problems.
错误原因： 主句缺少主语
改正：when a politician wants to investigate poverty problems in a city, he needs to learn about the daily life problems in the city.
3.Taking rope skipping every morning for example, which let people maintain a clear mind, promote the metabolism and increase the immune system.
错误原因：句子结构不对
改正：Take rope skipping as an example. Rope skipping helps people maintain a clear mind, promote metabolism, and strengthen immune system.
4.Because the excessive consumption of products is pervasive. It is crucial to take measures to mitigate the pollution.
错误原因：标点符号错误
改正：Because the excessive consumption of products is pervasive, it is crucial to take measures to mitigate the pollution.
5.Regular change of jobs makes one greatly enriches one's experience of the world, therefore, one can have brighter career and enjoy precious memory in the future.
错误原因：therefore不能连接两个简单句
改正：Regular change of jobs makes one greatly enrich one's experience of the world. Therefore, one can have brighter career and enjoy precious memory in the future.
6.From my own perspective, scientific research is significant for the development of a country, it facilitates the revolution of science and prompts the progress of technology.
错误原因：两个简单句缺少连词
改正：From my own perspective, scientific research is significant for the development of a country, because it facilitates the revolution of science and prompts the progress of technology.
