Thank you for using the timer!
We noticed you are actually not timing your practice. Click the START button first next time you use the timer.
There are many benefits to timing your practice, including:
I think (E) as well. Here is my analysis. Let me know if it is wrong
A. Five hundred million different species of living creatures have appeared on Earth, nearly 99 percent of them vanishing. "nearly 99 percent of them vanishing" grammatically incorrect
B. Nearly 99 percent of five hundred million different species of living creatures that appeared on Earth have vanished. Not sure about the use of "nearly" here! This makes me think there is more than "five hundred million different species"
C. Vanished are nearly 99 percent of the five hundred million different species of living creatures that appeared on Earth. "Vanished are" is awkward
D. Of five hundred million different species of living creatures that have appeared on Earth, nearly 99 percent of them have vanished. Should have "the" to identify "five hundred million different species" specifically.
E. Of the five hundred million different species of living creatures that have appeared on Earth, nearly 99 percent have vanished. This one looks best.
Between B & E, I pick E as present perfect for "have appeared" is much better than the past tense for "appeared". The latter one refers to a completed action and implies those creatures appeared in the past and disappeared at present.....
I will also Pick E. The reason given by Hcgmat is perfect!. I have to same reasoing for picking E. In B it seems "they appeared" it seems that the action is already completed.. and now no more exist..?
here is my 2 cents, please correct me if I am wrong
in B prepositional phrases "of living creatures" "on Earth" nicely modifies subject species
in E, dependent clause "Of the five hundred million different species of living creatures that have
appeared on Earth" is set off by another dependent clause "nearly 99 percent have vanished". I am not really sure what the second one is modifying. At least one of them should have been an independent clause
More over, construction of prepositional phrases
of the ..(.......) of living creatures .....(), seems little awkward
I guess you are looking in the opposite way. Well E read "present perfect" that is action is still in process rt? Which Sounds better to my ears may be I am missing something. Whereas in B it reads " that appeared" well seems that the action is completed no more species are evolved now.
You c what I am trying to say?
Well I guess have to go and ask my prof now!
I hate bugging him. I am having some real problems with tenses.
'E' has two present perfect forms which is not correct.
The sentence uses 'the five hundred million' to denote the number of species and it goes on to use 'have appeared on earth' which means that the number of living creatures are still increasing but that is not the intent of the sentence and moreover I do not think that one can use two present perfect forms in one sentence.
Hey noboru, the below explanation should help. I was not sure if I could paste the link in the forum, hence copying the explanation. The explanation is by a very good manhattan staff and so I can vouch the authenticity of the same.
I'm not a fan of this source overall.
I'd go with E. Besides being generally awkward, B has a verb tense issue. It says "species that appeared" on earth. Appeared is simple past but, in this case, we want present perfect. We use past tense to discuss something that is completely over; we use present perfect to discuss something that started in the past but is either still true or still going on in the present. It is still true that the species appeared, so we want to say "have appeared" - which answer E does use and answer B does not.
Whats the diff when I say - Of the five hundred million different species vs Of five hundred million different species
If you insert the word "the" you are indicating that you have already been talking about these species and you're referring to them again. Without the "the" - it's the first instance in which you are talking about them.