语法 - past
- Past
- Past continuous (I was working)
- Past continuous or past simple?
- Past perfect continuous (I had been working)
- Past perfect simple (I had worked)
- Past perfect simple or past perfect continuous?
- Past perfect simple or past simple?
- Past simple (I worked)
- Past simple or present perfect?
- Past verb forms referring to the present
- Past: typical errors
- Used to
