How important are these tenses - future perfect, present perfect continuous, past perfect continuos, futire perfect continuos

i found a couple of qsns in OG that required answer like "are studying" / "have been studying" ( when i was expecting "have studied" - present perfect )

i poured over the verb-tense part of Manhattan guide and when i took the corr OG part found lil shaky - as these verb forms ( mentioned above) were there - how frequently are they tested ? is it because these are not too important that the Manhattan Guide doesnt mention them ?


Thanks in advance
Sankar

Sankar, the progressive (continuous) tenses, as well as the future perfect tense, are not explicitly tested on the GMAT. The example problems that you cite might include such tenses, but these tenses will not be the differentiating factor between or among answer choices. For example, the "are studying" v. "have been studying" distinction on the GMAT will be between the present "are" and the present perfect "have been." I have yet to come across an Official GMAT problem that requires a knowledge of tenses other than the simple tenses and the past and present perfect tenses.

If you have a specific example problem that suggests differently, please reply with its citation - I would be interested to see it.

-dan