by thanghnvn Mon Mar 05, 2012 4:16 am
Ron,Stacey, pls, help. pls, come back to had done.
Less than 35 years after the release of African honeybees outside Sao Paulo, Brazil, their descendants, popularly known as killer bees, had migrated as far north as southern Texas.
A) Less than 35 years after the release of African honeybees outside Sao Paulo, Brazil,
B) In less than 35 years since releasing African honeybees outside Sao Paulo, Brazil,
I think "less than ...." shows a specific POINT of time at which descendents HAD DONE. we need a specifit POINT of time to show that an action HAD FINISHED at that point of time
in B, "in less than ...." shows a DURATION of time. Past perfect needs a specific POINT , not DURATION of time to show that an action had finished at that point. This is why B is wrong.
Past perfect can NOT go with DURATION OF TIME showned.There are 2 cases.
1. Past perfect needs a point of time which show the starting of the action and dose not need a point of time which show the ending of the action. The ending of the action is the point of time of speaking-in the past.
2. Past perfect needs a point of time (in past) which shows the ending of the action and dose not need a point of time which show the starting of the action. In this case, past perfect said that at that poit of time in the past, the action had finished. This is the case, choice A in above problem shows.
in short, past perfect need only one of specific point of time in the part, the poit of time at which the action begins or the point of time at which the action ends
Ron,Stacey, Manhantan expert. pls, confirm my idea. Am I correct?