1.employment指受雇于他人,领取工资以谋生计,并且是比较固定的工作，倾向于表达职业，雇佣.例如：
His employment is that of a bookbinder.他的职业是装订工.
跟work和job的区别还是挺大的
2.work是用语表示工作或职业最常用的词,它可以用来泛指一切长期性的职业,包括脑力劳动和体力劳动,通常代替employment和job.不过work多用来指“工作”本身,平常我们每做一件事无论大小,都可以称为work.
3.job非正式用语,泛指一份固定的赚钱工作,不论是否需要技术和特殊训练.该词在口语中广泛使用.例如：
She has a good job in a bank.她在银行里有份很好的工作.
work,job这两个词虽然都有“工作”的意思,但却是
近义词.
work 作名词,有体力或脑力劳动的意思(在这一意义上的
同义词有labour,toil),又有作为职业概念的“工作”的意思(在这一意义上的同义词有employment,occupation,calling).
I like garden too,but I don't like hard work.
我也喜欢花园,但是我不喜欢辛苦的劳动.
You have done a day's work in three hours.
你在三个小时内完成了一天的工作.
The children were at school,my husband was at work and the house was quiet.
孩子们上学去了,我丈夫去上班了,所以家里很安静.
Work on it had begun before my sister left.
这座房子的工程在我姐姐离开之前就已经开始了.
He is finding his new work far more exciting.
他现在发觉自己的新工作更加令人兴奋.
He is now out of work.
他现在失业了.
job 作为“工作”解,其实有两层含义：一个是“干活”的“活”,一个作为职业的“事”.job作“干活”的“活”解时的同义词有task,duty,assignment等；job作为职业的“事”解时有如下的同义词：position,place,situation,post等.
When you start a job,you must stick to it.
一旦你开始了一件工作,他就得持之以恒.
It was his job to repair bicycles and at that time he used to work fourteen hours a day.
修理自行车就是他的话,而且常常是一天要干14个小时.
I'm not going to wash the dishes,that's your job.
我不洗那些盘子,那是你的事.
He then asked me how my brother was and whether I liked my new job in London.
然后,他问我的兄弟可好,又问我是否喜欢在伦敦的新工作.
Alf's wife has never discovered that she married a dustman and she never will,for Alf has just found another job.
阿尔夫的妻子从来没有发现自己嫁给了一个清洁工,而且她再也不能发现自己丈夫是清洁工了,因为阿尔夫刚刚找到一种别的工作.
He is out of a job.
他现在失业了.
注：用英语表达“失业”,work和job这两个词都可以用,但是如果用job就必须用
不定冠词a,如果用work,则不用不定冠词.