By Affirmative sentences, Present perfect

My grammar book says "present perfect continous is usual in negative sentences with all verbs" This seems a little peculiar as a general principle stated 'out of the blue'. Were the authors trying to draw a contrast with the use of the present perfect in affirmative sentences with only...

Hi Manikandan, The Perfect Tense is a very large topic, though I'll try to explain some of the basic rules to you about the Present Perfect. (I did the Past Perfect in a recent post) The Perfect tense consists of HAVE + PAST PARTICIPLE and it is used in the following cases: 1. An action that...