一般过去时：ago,yesterday,the day before yesterday,last week(year,night,month…),in 1989,just now=a moment ago
,at the age of 5,one day,long long ago,once upon a time,etc.
一般现在时：usually,often,always sometimes,regularly,near,occasionally,every year,every week.
由after,until,before,once,when,even if,in case,as long as,as soon as,the moment以及if,unless等引导的时间状语从句或条件状语从句中,通常用一般现在时代替将来时
现在进行时：
1、表示说话时正在进行或发生的动作.
例：Please don’t make so much noise.I’m writing a composition.不要吵闹.我正在写作文.
Let’s set off.It isn’t raining now.咱们出发吧.现在不下雨了.
这类情况常与now现在,at the present现在,at the moment现在,today今天,this week这个星期,this year今年等时间状语连用.
2、表示现阶段正在进行而说话时不一定在进行的动作.
We are working in a factory these days.这几天我们在一家工厂工作.
They are compiling a dictionary.他们在编一本词典.
这类情况常与today今天,this week这个星期,this evening今天晚上,these days现在、目前等时间状语连用.
3、现在进行时与always等副词连用时带有感情色彩.
He’s always quarrelling with others.他老喜欢跟别人吵架.
She is constantly worrying about her son’s health.她不停地为她儿子的健康担心着.
The boy is forever asking questions.那个男孩老是问问题.
