在英语中，副词用于修饰形容词以及副词。程度副词，顾名思义，就是对一个形容词或副词在程度上加以限定或者修饰的副词，告诉读者某事发生的频率高低。在英语中许许多多的程度副词，让我们看几个例子。(以程度副词的频率从高到低排序)
always - He always does his homework.
他总是写作业。
usually - They usually complete the work on time.
他们通常及时完成工作。
often - I often watch movies online.
我经常在线看电影。
sometimes - Jack sometimes comes over for dinner.
杰克有时候会过来吃晚餐。
occasionally - She occasionally asks a question.
她偶尔问问题。
rarely - They rarely have any homework.
他们很少有作业。
never - I never complain at work.
我从不抱怨工作。
学习了几个程度副词，那么问题来了。程度副词在句子里的位置是怎么样的呢这需要我们分情况讨论。
1.如果句子里有谓语动词(不包含助动词)，则把程度副词放在主谓之间
结构：主语+程度副词+谓语动词
Tom usually goes to work by car.
汤姆通常开车去上班。
Mary often asks me for help.
玛丽经常向我求助。
2.放在 be动词之后
结构：主语+ be+程度副词
Tom is often late.
汤姆经常迟到。
Anne isn't usually sick.
安妮通常不会生病。
Peter isn't always right.
彼特并非永远正确。
注意：如果我们把程度副词放在省略句中，则该结构不成立。
Is she usually on time?
她通常都准时吗
Yes, she usually is.
是的，她通常都是。
She never is.
她从不是。
口语中还有其他的习惯表达，也不必要遵循上述结构。
What are you doing here? Shouldn't you be at school?
你怎么在这儿你不应该在学校吗
I normally am at school at this time, but my teacher is ill.
通常这时候我应该在学校，但是老师生病了。
3.如果句中有多个动词(包含助动词)，则把程度副词放在谓语结构的第一个动词之后
结构：主语+助动词或情态动词+程度副词+主动词
I can never remember his name.
我总是记不住他的名字。
Anne doesn't usually smoke.
安妮通常不吸烟
The children have often complained about the playground facilities.
孩子们经常抱怨游乐场设施。
但在 have to句型中存在例外。
结构：主语+程度副词+ have to+主动词
We often have to wait for the bus.
我们经常要等公车。
She never has to do any housework.
她从不需要做家务。
4.省略句中可以把程度副词放在句首或句末(但通常较少放在句末)
结构 1：程度副词+主语+主动词
Sometimes we go to school by bus.
有时我们乘公交车去上学。
Often he waits for her after class.
他经常在课后等她。
Usually Peter arrives early for work.
通常彼特很早来上班。
结构 2：主语+主动词+程度副词
We go to school by bus sometimes.
有时我们乘公交车去上学。
They like to watch TV often.
他们经常喜欢看电视。
注意： always不能用于句首或句尾; never, seldom, rarely不用于句尾，且用于句首时常用于表达看法或观点。
Never has there been a better time to overcome our differences.
不会再有比这个更好的时机来克服我们的不同。
Rarely do we have an opportunity like this.
我们很少会遇到这样一个机会。
5.在问句中，把程度副词放在主动词前
结构：助动词+主语+程度副词+主动词
Do you often go to the cinema?
你经常去电影院吗
Did he sometimes leave the classroom?
他有时会离开教室吗
注意： never, seldom, rarely等带有否定意思的程度副词通常少用于问句。
6.在否定句中，把程度副词放在主动词前
结构：主语+助动词+程度副词+主动词
They don't often go to the cinema.
他们不常去电影院。
Peter doesn't normally want to come with us.
彼特通常不想来找我们。
注意： never, seldom, rarely等带有否定意思的程度副词通常没有否定形式。
