英语什么时候用过去式什么时候用过去分词什么时候用现在分词

英语什么时候用过去式什么时候用过去分词什么时候用现在分词

以下是过去分词的用法：
过去分词表示“被动和完成”(不及物动词的过去分词不表示被动,只表示完成).分词可以有自己的状语、宾语或逻辑主语等.
1)分词作状语分词在句子中作状语,可以表示时间、条件、原因、结果、让步、伴随等.分词做状语时,它的逻辑主语与句子的主语一致.作状语的分词相当于一个状语从句.【例如】
Accompanied by his friend,he went to the railway station.
2)“while ( when,once,until,if ,though等连词)＋过去分词”结构作状语时,有时可以在分词前加while,when,once,although,until,if等连词.【例如】
Once recovered,he threw himselfsintoshis work and made every effort to do it well.
3)分词作定语分词作定语时,单个的分词通常放在被修饰的名词之前,分词短语一般置于所修饰的中心词后面.过去分词修饰承受该动作的名词(即与名词是动宾关系).【例如】
We will go on with our experiment as soon as we get the added fund.
We can see the part of the moon lighted by sunlight.
4)过去分词可以在allow,ask,consider,desire,expect,feel,find,get,have,hear,imagine,keep,like,make,observe,order,permit,prefer,remember,request,require,see,urge动词等后面作宾语补足语.【例如】
After my encounter with her,I found myself greatly shaken.You should keep her informed of what is going on here.The teacher expected the students well prepared for the examination.
5)分词作表语分词作表语通常看作形容词来用.现在分词表示主语的性质,而且主语多为物；过去分词表示主语的感受或状态,主语多为人.【例如】
The film“Pearl Harbor”is really exciting.I am excited about it.
一般过去式的用法
1）在确定的过去时间里所发生的动作或存在的状态.
时间状语有：yesterday,last week,an hour ago,the other day,in 1982等.
Where did you go just now?
2）表示在过去一段时间内,经常性或习惯性的动作.
When I was a child,I often played football in the street.
Whenever the Browns went during their visit,they were given a warm welcome.
3）句型：
It is time for sb.to do sth "到……时间了" "该……了"
It is time sb.did sth."时间已迟了" "早该……了"
It is time for you to go to bed.你该睡觉了.
It is time you went to bed.你早该睡觉了.
would (had) rather sb.did sth.表示'宁愿某人做某事'
I'd rather you came tomorrow.
4) wish,wonder,think,hope 等用过去时,作试探性的询问、请求、建议等.
I thought you might have some.我以为你想要一些.
比较：
一般过去时表示的动作或状态都已成为过去,现已不复存在.
Christine was an invalid all her life.
(含义：她已不在人间.)
Christine has been an invalid all her life.
(含义：她现在还活着)
Mrs.Darby lived in Kentucky for seven years.
(含义：达比太太已不再住在肯塔基州.)
Mrs.Darby has lived in Kentucky for seven years.
( 含义：现在还住在肯塔基州,有可能指刚离去)
注意：用过去时表示现在,表示委婉语气.
1）动词want,hope,wonder,think,intend 等.
Did you want anything else?
I wondered if you could help me.
2）情态动词 could,would.
Could you lend me your bike?

过去式只能做句子的谓语【时态】，过去分词和现在分词 都是非谓语形式，除了不做谓语，其它都行