 The usages for the present perfect continuous tense are very similar to that of the present perfect tense But here the focus is on the action and the fact that it has been Continuing for some time leading up to the present. Let's have a look. We've got incomplete and ongoing activities with duration. I Have been teaching for 10 years Then we have our recently finished activities with present results So our recently finished activity is chopping trees, but the present result is he is tired So results in a sentence reading he is tired because he's been chopping trees