English grammar notes
Tense时态
| 时间 | 一般 | 完成 | 进行 | 完成进行 |
|---|---|---|---|---|
| 过去 | did | had done | was/were doing | had been doing |
| 现在 | do | have/has done | be doing | have/has been doing |
| 将来 | will do | will have done | will be doing | will have been doing |
不规则动词变化表
| 原型 | 过去式 | 过去分词 | 现在分词 | 第三人称单数 |
|---|---|---|---|---|
| do | did | done | doing | does |
| be | was(is,am)/were(are) | been | being | is |
| have | had | had | having | has |
| will | would |
从句
名词性从句
名词性从句放在后句，省略that不会导致语意混淆，所以可以省略。
名词性从句放在前句，省略that容易导致语意混淆，所以不能省略。
I don't know it.
your mother is sick.
I don't know that your mother is sick.
I don't know your mother is sick. (省略that)
因为由that所带动的名词性从句，语意完全没变，因此在口语和文章上常会把后句的that省略，以求精简。
that you often go to school late is not a good behavior.
名词性从句若放在句子开头，that不可以省略
定语从句
也叫形容词性从句，你细品。
The person that is in my room is angry.
The dog that is on the bed is lazy.
状语从句
so...that (如此...以至于...)
It is so hot that I want to swim.
He is so old that he can't play with us. (so是副词如此地，只能修饰形容词或副词)
He is so young that he can't gp to school alone.
He is such an old man that he can't play with us. (such是形容词 如此的，只能修饰名词)
He is such a young child that he can't go to school alone.
that = because
She is sad because she has lost much money.
= She is sad that she has lost much money.
句子简化（省略）
The book which is on the sofa is mine.
(which is 代表的是 the book is 重复了主语和动词)
The book is on the sofa.
The book is mine.
The book on the sofa is mine.
(on the sofa继续保有形容词的功能)
将形容词子句(定语从句)重复的主语、动词省略
The girl who is sitting on the chair is my friend.
The girl sitting on the chair is my friend.
The pen which is on the desk is yours.
The pen on the desk is yours.
将（主语重复的）名词性从句简化成动名词
一般来说动名词的写法比名词性从句精简，因此造句过程中常会把主语有重复的名词性从句简化成动名词的写法。
He said that he saw me before.
He said seeing me before.
改变句意的话不能简化
He said that you saw me before
名词性从句中没有重复的主语能省略，如果省略了you，句子的意思将变成“他说他以前见过我”，所以词句不能进行简化
重要单词
whatever 无论如何
概念
现在完成时：现在已经完成。
现在进行时：正在做。
现在完成进行时：没干完，已经干了一段了，正在干。
助动词
have这个词有两个功能 既可以是助动词，也可以是实义动词你首先要搞清楚
谓语动词 = 助动词 + 实义动词
助动词，帮助构成完成时态（have done或have been doing），它在这时没意思，就是个标志。
那什么时候知道它是实义动词呢，很简单，只要have后面出现了过去分词时，它们相加就构成了谓语。
I have had many friends.
第一个have是助动词，第二个have是实义动词的过去分词形式had。
实义动词，它放在实义动词的位置，搭配啥助动词，它就构成什么时态。你所经常看到的谓语动词都是简化版
I have a book.
I do have a book.
如果不理解的话，想一下，这句话的否定句：I do not have a book.这句话，助动词是do，实义动词是have。
词跟人一样，在不同的位置，身份不一样，虽然还是同一个人，你在学校是学生，你在家就是父母的孩子了。词本无义，意由境生。想学好英语，所有字母类语言都一样，先把形式记准，再去考虑翻译意思。
谓语动词的助动词只有下列这些：
| 助动词类型 | 包含 |
|---|---|
| do | do,does,did（过去或现在一般） |
| will | will,would（将来、过去将来） |
| have | have,has,had（完成） |
| be | am,is,are,was,were,been （be+done被动语态；be+doing进行） |
易混淆的单词
question 指主观存在的“疑惑、疑问”，所以是需要“回答（ answer ）的”。通常指由于对某事疑惑不解，因而提出问题等待回答。
question指通过提问或 提出需要别人解答的话题 ，如试卷中的问题。动词搭配是ask和answer
But "issue" means "something that you are discussing."
issue 国际上发生的大事或正在讨论的什么事。争议，需要讨论的。
难题（Problem）："Problem" refers to "the situation that can cause difficulties."
problem 指客观存在的和遇到的疑难问题，有时指较严重的问题，所以是需要“解决（ solve ， work out ）的” 。等待解决或决定的问题，尤指比较困难的数学、物理、化学等习题以及社会问题
难题（Problem）一般是有明确的处理意向或处理方案的，比如在高速公路上车子坏了，很明显需要把车修好，大家对这个问题没有争议，只是处理起来可能比较困难，这属于难题。
matter 表示“事情，麻烦”，指具有某种特征的事例。
| 单词 | 含义 | 例句 |
|---|---|---|
| through | 穿过 | The bullet went straight through him. |
| thought | 思考，想法，打算（think的过去式与过去分词） | I don't like the thought of you walking home alone. |
| though | 虽然，尽管，不过 | Though a talented player, he was completely eclipsed by his brother. |
| although | 虽然，尽管，不过，即使 | Although the sun was shining it wasn't very warm. |
| permission | n.同意，许可；许可证，书面许可，权限 | |
| promising | adj. 有希望的, 有前途的, 有出息的，v. “promise”的现在分词 |