语法是
1.非谓语动词使用不当
原：Comparing with the money people earns, the sense of achievement is more important.
改：Compared with the money people earns, the sense of achievement is more important.
评：此处是动词compare的现在分词和过去分词使用混淆了。在英语中，动词的现在分词往往表示的是主动的意思，过去分词则表示被动的含义。原句想表达的是“将成就感与钱相比”，“把…与…相比”是明显的被动含义，因此应该使用compared.
2. 时态混乱
原：Although I have no work experience when I was a teenager, I always dreamed about having a job.
改：Although I had no work experience when I was a teenager, I always dreamed about having a job.
评：虽然托福写作以议论文为主，为了表示客观性，基本上使用的都是现在时态，但是在举例的时候还是会涉及到一些过去时态，例如上面的句子，切记：主从句时态要保持一致。
3. 表述累赘
原：Internet plays an important and indispensible role in people’s life today.
改：Internet plays an indispensible role in people’s life today.
评：这个句子一看就知道是作者为了使用高级词汇而犯下的错误。明明已经有Important来表示重要性了，又强行加上了indispensible来表示不可缺少，，老美是不喜欢的!
4. 用词不当：用词不当包括词性混淆，同义词错用以及固定搭配错误等。
词性混淆：
原句：A large number of people hold the believe that students’ social activities should be the first priority.
改：A large number of people hold the belief that students’ social activities should be the first priority.
评：这个例子中believe是动词，belief才是名词形式。虽然发音相近，但是用法却完全不同。
同义词错用：
原句：It’s indeed that people are worrying about the increasing population.
改：It’s true that people are worrying about the increasing population.
评：虽然二者都表示“真的”，indeed却没有it’s indeed that…的结构，此处只能用true来表示。
固定搭配错误：
原句：As a friend and mentor, she drew from humor, a beautiful spirit and her faith in the Aboriginal culture to accomplish her work.
改：As a friend and mentor, she drew on humor, a beautiful spirit and her faith in the Aboriginal culture to accomplish her work.
评：draw from: 从……中汲取(经验等)， draw on:借鉴(经验等)作者本想使用一个高级的表达法，结果用错了，很可惜。
上述就是托福作文中常见的一些语法错误，建议大家在备考托福考试时给予语法一定的重视，打好托福考试基本功，能把一些音符生动的串联在一起弹奏一曲曲美妙的曲子。