Sentence Correction

The National Transportation Safety Board has recommended the use of fail-safe mechanisms on airliner cargo door latches assuring the doors are properly closed before takeoff and to prevent them from popping open in flight.

(A) assuring the doors are properly closed
(B) for the assurance of proper closing
(C) assuring proper closure
(D) to assure closing the doors properly
(E) to assure that the doors are properly closed

Tough one!...At least for me. Please keep on correcting me at every point which is wrong.


so we have 3 splits here:

1) for the assurance

2) assuring

3) to assure


I avoided 1) as GMAT doesn't PREFER noun forms (assurance).

Same goes for option C...CLOSURE is noun form.


Next I don't know how to choose between ASSURING and TO ASSURE. so what about option A?

I think in GMAT we should avoid VERB-ing form when there is any comma with VERB-ing. Is it right?

Now I am left with D and E.


In D option any verb we have infinitive "to assure" and VER-ing, both of which can't act as main verb. So I picked E.

Question: Do we need main verb in the underlined part? I see there is already a verb in non-underlined part "has recommended".

vishalwin wrote:
so we have 3 splits here:

You have to be careful with splits. It can be the case that what seems to define a split does not actually, because of differences in other parts of those answer choices that seem to be similar.

1) for the assurance

2) assuring

3) to assure


I avoided 1) as GMAT doesn't PREFER noun forms (assurance).

That seems simplistic. In the right context that noun form could be ok, but anyway the version you eliminated is rather awkward.

Same goes for option C...CLOSURE is noun form.

I think you would be better off eliminating C for the following reasons. Without doors, what is being closed is missing, and so the meaning becomes unclear and changed. Also, C can be eliminated based on what is discussed next.

Next I don't know how to choose between ASSURING and TO ASSURE. so what about option A?

I think in GMAT we should avoid VERB-ing form when there is any comma with VERB-ing. Is it right?

What you said is not exactly correct. A verb -ing form, or participle, can follow a comma or be used without a comma. The two constructions are used to convey two different things. Without the comma, the modifier modifies the noun directly preceding it. With a comma, the modifier generally modifies the entire clause that precedes the comma.

He saw a dog sitting out front. (Sitting out front modifies dog.)

We played in the front yard, running around all day. (Running around all day modifies the entire main clause.)

At the same time, what you said is partially correct, in that without the comma, assuring... seems to modify latches, creating a sentence that does not make sense, as the latches are not what is assuring that the doors are closed.

Now I am left with D and E.


In D option any verb we have infinitive "to assure" and VER-ing, both of which can't act as main verb. So I picked E.

Question: Do we need main verb in the underlined part? I see there is already a verb in non-underlined part "has recommended".

We don't need a main verb in the underlined part as there is already a main verb, and the underlined part is merely part of a modifier.

Maybe the tight way to pick E over D is via meaning. The meaning is not that the mechanisms assure closing the doors properly, i.e. that the process of closing the doors goes properly. The meaning to be conveyed is that the mechanisms assure that the doors are properly closed, after the process of closing them is complete.

Also, to assure closing somehow does not work idiomatically.

So the correct answer is E.