这些词之所以称为助动词，是因为它们帮助构成某种时态或某种表达方法。它们与动词的现在分词、过去分词或不定式结合，帮助构成各种动词时态：
I am coming.
我来了。
He has finished.
他已做完了。
I didnt see them.
我没看到他们。
它们与动词原形连用表示许可、可能、义务、推测等。具体用法见以下几节。这里只举少数例子：
He can speak French.
他会讲法语。
You may go.
你可以走了。
We must hurry.
我们必须赶快。
Labour, labourer, workforce, worker 与“工作”相关的四个单词
Football and soccer 两个词的区别
Accountability, liability and responsibility 的区别
Almost, nearly, more or less “差不多”的三个近义词
Infer vs conclude 两个易混词
To be on the same wavelength 意气相投
Talk nineteen to the dozen 说话很快，喋喋不休
At each other’s throats 唇枪舌战地争吵
Strapped for cash 手头紧
Butterfly numbers drop a mystery, say experts 英国蝴蝶数量下降现象令专家费解
Armed to the teeth 全副武装
Revise and review 的区别
Is breast cancer linked to night shifts? 乳腺癌与上夜班有关系吗？
Lose one's shirt 输得一干二净
Practical and pragmatic “实用的”两个词的区别
Emperor/empress 和 king/queen 的区别
Have egg on your face 狼狈不堪
Passion and enthusiasm 两个词的区别
Have your feet on the ground 脚踏实地
Under someone's thumb 受人控制
Burn a hole in your pocket 一有钱就想花
Knock your socks off 叹为观止
Tasmanian devil milk fights superbugs 袋獾乳汁可对抗“超级细菌”
A sense of belonging 归属感
Retailer, wholesaler, distributor, outlet 几个词的区别和用法
To pop the question 求婚
Work your socks off 拼命干活
Shopping for ‘shoes’ 不同种类的“鞋”
To wind someone up 捉弄、惹恼某人
Turn a blind eye 视而不见