I would like to know which tense form is suitable for referring to an action which continued over a period of time in the past. Simple past,past continous, past perfect or past perfect continous?
Eg:- I had worked as science teacher for 5 years (for instance from 2001 to 2006)
Depends on the context....
I worked as a teacher between 2001 and 2005
I was working as a teacher between 2001 and 2005
past perfect continuous
I had been working as a teacher for 4 years before I became redundant