英语学习

in,on,at

#### 总述
* in
  - 表示时间: 指代较长的时间(上午,下午,年,月,季节等
    - in the morning
    - in spring
    - in May
  - 在空间范围: 在...里面
    - in the box
    - in the house
  - 地理方位(大的地点
    - I live in ShangHai
    - In 2019, I lived in Shanghai
* on
  - 表示特定的星期几
    - on Monday
    - on Tuesday
  - 具体的日期 (某月某日
    - on the fifth of May 2019
    - on the first of May 2019
  - 空间范围,在物体的表 在...上面
    - on the table
    - on the ground
* at
  - 表示具体时间 (时间的某一点,某一时刻,具体年龄
    - at six o'clock
    - at noon
    - at the age of six
  - 某一点的位置
    - at school
    - at home
  - 与名次所有格连用
    - at my sister's
    - at the doctor's

There be

#### There be
There be+名词主语（人或物）+地点 主要用来表示“人或事物的存在”或“某地有某物”

##### 一般用法

###### 一般: 
当be后面接的是单数可数名词，则采用is；当be后面接的是复数可数名词，则采用are。如：

1. There is a man under the tree.
2. There are some apples on the table.

##### 否定:
There be的否定句一般是直接在be后加not，not可以缩略为't。如果原句中还有some，一般要改为any

1. There isn't a man under the tree
2. There aren't any apples on the table

###### 一般疑问:
There be句型要改为一般疑问句，只要把be提到句首即可。其肯定回答为：Yes, there is/are，否定回答为：No, there isn't/aren't。如果原句中含有some，也要改为any。如：

1. Is there a man under the tree?  | Yes, there is / No, there isn't
2. Are there some apples on the table? | yes, thre are / No, there are not

##### 特殊疑问句:
There be 句型的特殊疑问句主要有how many和how much做引导词两种情况。如：

1. How many students are there in your school? | There are five thousand students in our school (five thousand
2. How much money is there in your wallet? | There is a little money in my wallet. (a little

###### 反义疑问句:
There be的反义疑问句一般是以be作为反义疑问部分的助动词来用，它也遵循“前肯后否、前否后肯”的原则。如：

1. There is a man under the tree, isn't there?
2. There are some apples on the table, aren't there?

#### 主谓一致

##### 不可数名词作主语
当be后接的是不可数名词时，be要采用is；当其后接的是由表量的名词的复数所连接的不可数名词时，be要采用are

1. There is some bread on the table
2. There are three piece of bread on the plate

###### 就近原则
如果There be 后面是几个并列名词时，动词be的形式和最靠近它的那个名词保持数的一致。如：

1. There is an apple, two plates on the table
2. Therea are two apple, an plates on the table

##### 时态变化
There be 句型中的be可以有一般现在时、一般过去时、将来时和完成时的变化

1. There are some people talking loudly in the reading room
2. There was a car race in the town last year
3. There will be a meeting next Friday
4. There has been g greadt increase in population in the city in the past five years

##### 与情态动词的连用
There be句型也可以与情态动词连用。其基本用法结构为：There+情态动词+be+名词主语+其他成分。如：

1. There may be a great exhibition in Shanghai next year
2. Ther must be some cakes left in the box

##### 各种句型中的There be
There be句型也可以和be going to 、seem to 、appear to 、used to、be likely to 、happen to等常用句型连用。其基本用法结构为：There+特殊句型+be+名词主语+其他成分

1. There seem to be a big difference between the twins.
2. There is going to be a film in the village tonight.
3. There is likely to be a snowstorm.
4. There happened to be a man nearby.
5. There appeared to have been a tragic accident last week.

##### 与其它动词的连用
here be句型中的be有时会被替换为其他行为动词

1. There came a breeze
2. There lived a princess who is very beautiful

##### 与have的区别
There be和have都可以表示“有”的意思，此时两者的用法可以相互转化. 如:

1. There are many small rivers in the ancient town
2. The ancient town havs many small rivers

但是，只有There be能够用来表存在，侧重表达某地有某物，而have没有此用法

1. There are some trees in front of the hourse

##### There be的非谓语动词用法
There be 结构的非谓语动词形式是there to be 和there being 两种形式。在句中作主语、宾语和状语。

###### 作主语
1. There being a bus stop near my hourse is a great advantage

###### 作宾语
there to be可以用作expect、like、mean、intend、want、prefer等动词的复合宾语。如

1. I expect there to be no argument about this
2  People don't want there be another war

有时也会用作介词的宾语，其形式一般为there being。如

1. I never dreamed of there being any good chance for me

###### 作状语
作状语时，通常采用“there being”结构。如：

1. There being no one to help me, I had to do it all done