The new house's front door is secured by an electronic lock

[Sage Pearce-Higgins]

To be clear, the rule about semicolons is that they must contain two complete sentences (not fragments). Answer choice D does this; the part after the semicolon is a complete sentence and has the verb "allows".

Tim was referring to answer choice A, in which the noun "feature" is followed by a 'that' modifier and no verb, thus making it a fragment.

[sg2010]

@Tim: Manhattan said that "not only...but also" is not acceptable. Would appreciate knowing if this was a typo on manhattan's part (which it seems to be since the correct answer uses not only but also).

Quote from the CAT on why E is wrong: (E) The idiom not only X but also Y is used to indicate that two ideas reinforce each other; its usage doesn’t make sense for two contrasting ideas.

Explanation also includes this: The modifier without physical keys is misplaced; the point is that the residents can lock and unlock the door without using a key, not (as this choice implies) that residents without keys can lock and unlock a door by some other, unexplained means.

What is "to lock or unlock the door" modifying? Answer that, and you'll see the problem (hopefully).

And who said that "not only ... but also" is not acceptable here??

[sg2010]

Apologies for the multiple iterations. I am trying to fully understand the SC problems that have ",.. that".

To be explicit, in the original sentence pasted below, the part before that, bolded, HAS TO BE a complete sentence. Since there is only a noun and no verb, therefore it is not a sentence. In order to correctly use "that," the part before that and the part after that have to be independent clauses? Is that correct?

"The new house's front door is secured by an electronic lock; a feature that not only allows residents to lock and unlock the door without physical keys, but also may prevent them from entering the house during a power outage."

To be clear, the rule about semicolons is that they must contain two complete sentences (not fragments). Answer choice D does this; the part after the semicolon is a complete sentence and has the verb "allows".

Tim was referring to answer choice A, in which the noun "feature" is followed by a 'that' modifier and no verb, thus making it a fragment.

[Sage Pearce-Higgins]

You're right about the use of "that": it introduces a noun modifier. The basic rule is that we should be able to remove the noun modifier and still have a complete sentence. To be clear, the complete sentence may not be before the "that" modifier. Take the following example:

The house that stands next to mine is red.

I've put the "that" modifier in italics here: you can see that the sentence 'The house is red.' works okay on its own. I encourage you to familiarize yourself with the material in the SC strategy guide on Sentence Structure and Modifiers.

[RAHULS852]

Hi Sage/ Manhattan expert,

I am unable to understand right usage of " but may also"
In option D is use of "but may also" different from "but also" ?
"Not only X but also Y " is correct idiom structure but we can not use this structure here because one effect is positive and another effect is negative.

In D "but" is used to show contrast.
Tarun loves football but may also love hockey.
Tarun not only loves football but also loves hockey.

Is "but" in D used in the same way as in first sentence ?

Regards,
Rahul Singh

[Sage Pearce-Higgins]

"Not only X but also Y " is correct idiom structure but we can not use this structure here because one effect is positive and another effect is negative.

Agreed. This construction does not show contrast, but provides two things going in the same direction. Thus it's inappropriate for the sentence above.

In D "but" is used to show contrast.

Agreed: we have one positive and one negative consequence of the electronic lock.

Tarun not only loves football but also loves hockey.

This sounds fine to me: the two facts about Tarun are similar.

Tarun loves football but may also love hockey.

This one sounds odd to me: it's not really a contrast. Of course, there's some debate to be had over where exactly the boundary is between similar facts and contrasting facts (I agree that there's some contrast between the sports). I would think that the following sentence is clearer: 'Tarun loves football, but he may also love hockey.' Breaking the sentence into two clauses makes the contrast clearer. Without the extra 'he', my ear expects a simple opposite: 'Tarun loves football, but not hockey.'

Is "but" in D used in the same way as in first sentence?

Yes, it's used for contrast. Here's a similar example: 'Tarun loves football, but often misses training due to his other commitments.'

[RAHULS852]

Thanks Sage.

I have one more question:
Can "but also" use without "not only" ?

Tarun is an instructor and also a scientist. ( Means Tarun's main job is as an instructor and he also works as a scientist)

Tarun is an instructor but also a scientist.

Tarun is not only an instructor but also a scientist.

1 & 3 are fine to me.
But i am not sure about 2nd one.
Sorry for bothering you again and again.

Regards,
Rahul Singh

[Sage Pearce-Higgins]

No bother at all. I would say that your second example (Tarun is an instructor but also a scientist.) is not acceptable on GMAT. It's important to note that the construction "X but Y" is for contrast, but the construction "not only X, but also Y" is used for two things that reinforce each other. It isn't clear which category your example fits into.

[RAHULS852]

Thanks Sage.

Actually I forgot that "X but Y" is used for contrast. Now I am clear on this concept.

Regards,
Rahul Singh

[Sage Pearce-Higgins]

Good to hear that.

[JbhB682]

Hi - for option D, three quick questions

a) this feature allows residents to lock and unlock the door without physical keys ... Here 'Allows" is not a helping verb but a regular action verb (present tense specifically) ?

b) but may also prevent them from entering the house... Here "MAY PREVENT" is a helping verb with a tense, that is present tense ?

c) Can action verbs be parallel to helping verbs ? When I tried to make a sentence, I fail
Example : This cow smells great but runs all over the place

This seems like a strange sentence, something I wont say because smells great is a helping verb whereas runs is a regular action verb.

Example : I would keep helping verb parallel helping verb
This cow smells great but IS RUNNING all over the place

Here smells great and IS RUNNING are both helping verbs

[esledge]

(a) Yes, “allows” is just a stand-alone present tense verb (with no helping verb).

(b) The “may” helper (or modal) expresses possibility: the lock won’t necessarily prevent entry, but it might. It’s not necessarily either present or future tense, as it’s still hypothetical.

(c) There’s no helping verb in “smells great”; the only verb there is “smells” and “great” is just an adjective. That sentence is correct because “smells” and “runs” are both present-tense verbs that the cow does. I think you are looking for an example like this:

This cow has experienced many difficulties, but now enjoys life at the animal sanctuary.

Yes, one part of the parallelism can be a (plain) action verb, and the other part can be a verb that has a helping verb. The parallelism is between the entire bolded verbs (including helper, if present), not just between “has” and “enjoys” above.

Example : I would keep helping verb parallel helping verb
This cow smells great but IS RUNNING all over the place
Here smells great and IS RUNNING are both helping verbs

No, "smells" is not a helping verb; only “is” is a helping verb. This sentence is not wrong, again because “smells” and “is running” are both things that the cow does. However, I’d still prefer the parallelism of “smells” and “runs,” unless there is a compelling meaning reason to use the present progressive “is running.”