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Hi,

Hope you find this thread useful: http://www.manhattangmat.com/forums/australian-embroyologists-have-found-evidence-t2938.html

Ron Purewal:
the two constructions have different meanings.
is descended --> used to talk about evolution, ancestry, etc. (as in this context)
has descended --> has moved, literally or figuratively, in a downward direction: the larynx has descended (literally) during the process of human evolution; our culture has descended (figuratively) into mindless entertainment

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- VK

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Thanks, but i have already read the posts on various forums. On one of them Ron said that
1) "is descended" is passive
2) "is descended from" is indeed a description of a condition in the present. it's the same thing as "is a descendant of".. (see last post http://www.manhattangmat.com/forums/sc-is-descended-or-has-descended-t7211.html)

I did not get that. how would you make passive of sentence - "Eric is a son of Samantha"

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Well, as I see, to make a passive construction, only linking verb ('to be') is not enough; there must be a action verb, in past participle form.

Over to the experts.

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- VK

I will (Learn. Recognize. Apply)

The answer is A .experts please let know the answer. A correctly uses 1)Evidence + suggests and 2)"is descended"

Experts can you please help

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IMO 'is' = present tense and 'descended' = participle (adjective) describing 'the elephant'. 'Has descended' incorrectly changes the tense to present perfect.

1) Can an erudite address above query.
2) Why present tense is correct. Here's an analogy,"humans evolved from apes" but this correct sentence is in past tense

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be + past participle form is a passive structure. But at the same time, the verb should be a transitive one as an object is needed. In you example,

Eric is a son of Samantha. --> here the main verb is a "be" verb, so this cannot be converted into passive.

I would not worry about tenses in this SC - as we are not given a split between past and present.

Option B,C and d can be directly eliminated due to the presence of the active voice - Elephant cannot do the action of "descended".

This one is in active voice and quiet similar to the other part of the sentence - "trunk originally evolved..."

But the analogy with "the elephant is descended .." does not hold with this one.

Hope this helps !!

Ron said i.e. Elephant is descended from an aquatic animal is same as Elephant is a descendant of aquatic animal
Elephant is a descendant of aquatic animal is of the form Eric is a son of Samantha but we cannot have passive for this sentence. what's the reason, i agree with object concept but that should apply to elephant sentence as well


In similar way, Humans cannot do the action of evolving but we say "humans evolved from apes". I think both sentences - elephant and human ones - are intended to describe that who were the ancestors of these living beings

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IMO the elephant desended on its own (there is no external agency making elephant to descend - atleast its not clear from sentence) and therefore we cannot convert into passive. This Avik has rightly pointed is "inTRANSITIVE VERB".

In passive we require a logical subject (generally denoted by "BY" - sometime this may NOT be present in sentence but will be obvious). Therefore even though "IS DESCENED" takes the passive construction of (TO BE + PAST PARTICIPLE), it is NOT passive as there is no logical subject of IS DESCEND.

IMO Ron intends to say "is descended from" and "is a descendant of" are same in meaning NOT MATHEMATICALLY, as IS DESCENDED FROM (TO BE + PAST PARTICIPLE+PREP) while IS A DESCENDANT OF (TO BE + NOUN)

D vs E
HAS DESCENDED implies Descending started sometime in past and still continues - is elephant STILL EVOLVING FROM acquatic animal? We cannot say from sentence - the original sentence says its a one time activity by using IS DESCENDENT.

I can also infer this sentence 2 WAYS:
1) "elephant HAS EVOLVED FROOM ANIMAL ..AND ..TRUCK HAS EVOLVED.." or
2) "elephant HAS EVOLVED FROM ANIMAL ..AND ..TRUCK EVOLVED.."

(1) We can misinterpret that both elephant and trunk CONTINUES TO EVOLVE while in (2) we can interpret that elephant CONTINUES TO EVOLVE but trunk ALREADY EVOLVED. Two different interpretation

Furthermore Use of THAT...AND THAT...makes things very clear in long sentences and generally preferred.

HI All,

I have one basic doubt in finding the noun in the below sentence, can anybody please help me what are the nouns in this sentence below

" Keli's ambition is to win the state lottery"

Best Regards,
Subrat

I think you meant SUBJECT (doer of the sentence) - AMBITION

There are 2 nouns in the sentence - AMBITION, LOTTERY

"is descended" is indeed passive. The significance of passive is that the gramatical subject is not doing the action. Here we can't say that the elephant descended on its own. Logical subject (by X) is generally deleted as we are not concerned who is the doer of the action, but on whome the action is being done.

The police caught the thief. - in this sentence the main topic is "the police" ( subject actually defines the topic).
The thief was caught. - in this sentence the main topic is "the thief" ( subject actually defines the topic). When this sentence is written the doer of the action is not the main consideration for the author.

here, logically we can say -

The elephant descended into the river.
The elephant descended from the aquatic animal - here it implies that the elephant is doing the action of its own. How can an elephant do that ?

"evolved" is different from the verb "descended".

1. "Evolved" is always a intransitive verb, but "descended" can act both as transitive and Intransitive verb.

He quickly descended the stairs. - here its an transitive verb.

2. "evolved" - the subject is the implied object. So when we use this kind of verb, it is implied that the subject is not doing the action. E.g : happened, rolled.... So even the sentence being active, the subject do not perform the action.

The tsunami happened in X.
The ball rolled down the stairs.

The elephant evolved from the aquatic animal - this is active, but correct. When we are using "evolved", it is always taken into consideration that "elephant" cannot do the action of evolving of its own. So in the second part of the sentence - "trunk originally evolved" is correct even being active.

D can be eliminated based on active voice - "has descended", which is again active.

I think I went too quickly while writing my post. I agree with Avik that IS DESCENDED is passive.

Just found another link (great explanation from Ron for everything)

http://www.manhattangmat.com/forums/sc-is-descended-or-has-descended-t7211.html

http://oald8.oxfordlearnersdictionaries.com/dictionary/descend