In Present tenses^x, Difference between^x, Auxiliaries^x

Present Perfect is formed with the auxiliary have and the past participle of some verb: have seen, has done, have lived. Present Perfect Progressive is formed with the auxiliaries have and been and the present participle of some verb: have been seeing, has been doing, has been living.CJ

One such grammatical distinction causing much confusion is the use of the modal auxiliaries ‘may’ and ‘might’. When used in the present tense, the two modals are almost transposable, as the difference between the two is merely a very small degree of certainty. However, it has become common...