我们一直在不断的学习语法规则，为什么呢?因为语法知识是用英语交流的基础。
1. Memorize 3 Fundamental Capitalization Rules
记住三个基础的大写规则
The first word in a sentence. You should always capitalize the first word in a sentence regardless of what type of word it is.
大写句子里的首字母。不管句子里的第一个单词属于什么类别，都要大写其首字母。
Proper nouns (names). These include the names of people, places, days and months, companies, etc. For example: Matthew, Helen, France, Tokyo, Mississippi, Saturday, January…
专有名词首字母大写。包括：人物的名字，地点，日期，月份，公司等。例如：马修，海伦，法国，东京，密西西比州，星期六，一月等….
Honorifics and titles, as well as their abbreviations. Mr., Mrs., Miss, Doctor (Dr.), President, Lord, etc.
大写敬语及头衔的首字母。例如：先生，夫人，小姐，医生，主席，公爵等。
2. I and Me Aren’t Interchangeable
I和Me是不可互换的
I and me are’t interchangeable. They are used in different grammatical constructions. I is a pronoun that serves as a subject of a sentence. For example, Matthew and I went for a walk, both I and Matthew are subjects of the sentence while went is the verb. Me is a pronoun that serves as an object of a sentence. Me is needed when someone else is performing the action.
I和 Me是不可互换的,它们用于不同的语法结构。I 是一个代词，是一个句子里的主语。例如：马修和我出去散步，这里I 和Matthew 都是句子里的主语，而went是一个谓语动词。Me是一个代词，作为句子里的宾语。当其他人需要执行某个动作时就需要使用me。
To use the example above: Matthew took me for a walk. Matthew is the subject and me is the object in the sentence. Knowing your subjects and objects will help you use these types of pronouns flawlessly!
使用上面的例子：马修和我一起出去散步。Matthew是句子里的主语，me是句子里的宾语。明确你的主语和宾语会帮助你无误地使用这些介词。
3. Be Careful When Using Your and You’re
小心使用Your和You’re
This is probably the most common mistake on the internet today! Your and you’re sound absolutely the same, but they have very different meanings and uses.
这可能是今天网络上最常见的错误!Your和You’re的读音听起来完全一样，但是它们的意义和用法完全不同。
Your is a possessive determiner that attributes something to you:
Your是一个物主限定词，用来限定属于你的东西。
Your work is impressive!
你的工作简直令人钦佩!
You’re is a contraction of you are:
You’re 是you are的缩写。
You’re a very successful writer. (You are a very successful writer.)
你是一个非常成功的作家。(你是一个非常成功的作家。)
Mistakes happen when possessive pronouns are confused with verb contractions, even among native English speakers. Often, you may see phrases like your wrong (instead of you’re wrong), you’re sister (instead of your sister), etc. These are grammatical errors. They’re easy to avoid. Don’t repeat them!
物主代词和动词缩写混淆的错误经常出现，即使是本族语使用者也常犯这样的错误。通常情况下，你经常会看到your wrong(而不是you’re wrong)，you’re sister(而不是your sister)等。这些都是语法错误，很容易避免，所以不要重复犯错!
4. Be Careful When Using Their, They’re and There
小心使用Their, They’re 和 There
这是代词，缩写以及副词混淆的一个例子。Let’s analyze each of the words in question.下面让我们在具体的例子中分析每一个词。
Their is a possessive determiner. When using their, you indicate that something belongs to them. For example, Their car has broken down.
Their 是一个物主代词。当使用their的时候，你的意思就是某物是属于他们的。例如，他们的车坏了。
They’re is a contraction of they are. For example, If they’re not coming, I’m leaving early. (If they are not coming, I’m leaving early.)
They’re是 they are 的缩写。例如，如果他们不来，我就早点离开。(如果他们不来，我就早点离开。)
There is an adverb indicating a location of something. For example, Your keys are over there, on the table.
There 是一个副词，说明某物的地点。例如，你的钥匙在那，在书桌上。
Once you understand the difference between these three words, you won’t make a mistake like their nice (instead of they’re nice) or there dog (instead of their dog) ever again!
一旦你理解了这三个词之间的差别，你就不会犯类似的错误，例如，their nice(而不是they’re nice)或者there dog(而不是their dog)!
5. There’s a Subtle Difference Between Must and Have To
Must 与Have To有细微的差别
Modal verbs in English serve to indicate possibility, obligation and more. The most common examples of modal verbs include can, may, must, will and shall. Must is the one indicating an obligation or a necessity to do something.
英语中的情态动词用来说明可能性，义务或者其他。最常见的情态动词包括can, may, must, will和shall。Must是用来说明义务以及做某事的必要性。
I must wake up early to catch a morning train.
我必须早点起来去赶早车。
However, we could also say:
然而，我们也可以说：
I have to wake up early to catch a morning train.
我不得不早点起来去赶早车。
语法上来说，他们都对，但是有什么细微的区别吗?有!
The difference between must and have to is subtle. Both refer to an obligation, but must indicates an opinion or suggestion. Have to is an expression of a more objective obligation coming from an outside force.
Must与have to之间的差别是细微的。两者都指义务，但是must是指意见或者建议。Have to指来自于外部世界的客观义务。
因此说某个人必须做她的家庭作业是你的意见。说她不得不做她的家庭作业代表着她必须这样做。在非正式的场合must和have to不可互换。在正式一点的场合，熟知must和have to的区别你就可以把它们区分开。
