be to .be going to .be going有什么区别?都表示一般将来时啊

be to .be going to .be going有什么区别?都表示一般将来时啊
be to .be going to .be going有什么区别?都表示一般将来时啊

be to .be going to .be going有什么区别?都表示一般将来时啊
一.小窥 “be to do” 的用法
一般说来,“be to do” 这个结构有两种语法意义,其一是连系动词 be+ 动词不定式做表语,其二是 be to 是一个独立词汇单位 ,具有情态含义 ,可以把它叫做情态习语 (modal idiom) .
一、 be + 动词不定式 ,不定式做表语 ,表示主语和表语在概念上是等同的.如：
The problem is to find a solution.
His plan is to clean the room.
My wish is to be a doctor.
二、 be to + 动词不定式中的 be to 用作情态习语 ,这时的 be to do 表示 :“ 计划 ” 、 “ 安排 ” 、 “ 义务 ” 、 “ 应该 ” 、 “ 可能 ” 、 “ 命运 ” 等.(have to,ought to) .如 :
He is to have a holiday.( 表示将来 )
The committee is to meet today.( 表示计划、安排 )
You are to go to the hotel where rooms have already been booked for you.
1.表示 “ 将 ” 、 “ 计划 ” 、 “ 安排 ” .( 意思接近于 be going to) 如：
Their daughter is to get married soon.
Who is to question him
It was the last film at the cinema ,which was to close next day.
After dinner they were to go to a movie.
was/ were to do 表示过去曾经计划要做的事,或者过去应当做的事,而且从现在的角度来看已经实现了.如：
I felt nervous because I was soon to leave home for the first time.
I was to play Juliet.
The expedition was to start in a week's time.
was/ were to have done,表示 “ 本打算 ” 、 “ 本计划 ” 或 “ 本应当 ” 做的事而没有做成或没有发生.如 :
I was to have seen him last Wednesday,but he didn't come.
We were to have been married last year.
2.表示 “ 义务 ” 、 “ 应该 ” .( 意思接近于 should ,must ,ought to ,have to) 如：
No one is to leave the building.谁也不得离开这楼房.
You are not to smoke in this room.=You are not supposed to smoke in this room.
You are to be back by 10 o'clock.你必须十点以前回来.
3.表示可能性 ,相当于 can,may 如 :
Such books are to be found in the library.这样的书在图书馆里就能找到.
Not a single sound was to be heard.一点儿声音也听不到.
Not a soul was to be seen.看不到一个人影.
She was nowhere to be found.哪儿也找不到她.
She was never to see his wife and family again.
5.表示 “ 命运 ”,将来必然要发生的事 ,译作 “ 注定 ……” .如：
He came to power,but he was to play dearly for it:soon he was assassinated.
The worst is still to come.
They said goodbye,little knowing they were never to meet again.
6.用于 “if…were to do” ,表示虚拟语气.如：
If it were to rain tomorrow,the sports meeting would be put off.如果明天下雨 ,运动会就会延期.
Exercises:
1.This film _____ this Sunday.
A.is going to show B.is showing C.is to be show D.will have been show
2.The students were told that they ____ at the school gate at 2:00 the following afternoon.
A.met B.will meet C.were to meet D.were met
3.The house ______ ready today but as there has been a builders' strike it is still only half finished.
A.is B.was to be C.was D.was to have been
4.In such dry weather,the flowers will have to be watered if they _________.
A.have survived B.are to survive C.would survive D.will survive
5.How _______ I ______ what has become of him?
A.am; to know B.am; knowing C.was; to know D.will; know
6.______ he ________ tomorrow,I would go to meet him at the station.
A.Were; to come B.Was; coming C.Did; come D.Would; come
二.be going to do 强调的是一种当时正在进行时的动作或将来要进行的某种动作.to 后面接的是动词原形.
三.如果be going 后面直接加动词,那么going就是去哪的意思,这就变成了简单的现在进行时,比如i'm going home.

前者表示带有一定的含义，或者说有注定怎样的意思，后者主观性较强，并不表示一定会怎样