Both tenses are used to express that an action began in the past and is still going on or has just finished. In many cases, both forms are correct, but there is often a difference in meaning.
- Present Perfect Simple: mainly express that an action is completed or emphasise the result.
- Present Perfect Progressive: emphasise duration or continuous course of an action.
Result or duration?
Do you want to express what has happened so far or how long an action has been going on yet?
| Present Perfect Simple | Present Perfect Progressive |
|---|---|
| Result (what / how much / how often) |
Duration (how long) |
| I have written 5 letters. | I have been writing for an hour. |