A new study on human sleep patterns has found that people take longer

OFFICIAL EXPLANATION



THE PROMPT


• Meaning?
→ The sentence describes three things about human sleep patterns in the days close to a full moon: people take longer to doze off, people sleep less deeply, and people sleep for a shorter duration.
These "list items" must be placed in proper parallel structure:
A, B, and C
or
A, and B and C (in which B and C are compound "items" on the list)

• Structure? Parse the sentence (diagram it loosely in a vertical way)
A study has found that people
. . . . . . . take longer to doze off
. . . . . . . sleep less deeply, AND
. . . . . . . sleep for a shorter duration

THE OPTIONS

• the word sleep must be repeated in the third list item
→ Otherwise, the sentence says that people take a long time to go to sleep, sleep poorly, and [missing verb] for a shorter duration.
→ The word and is a parallelism marker; all the items on the list must be verb phrases (verb + other stuff)
" [people] . . . for a shorter duration" is not a verb phrase. No verb exists.

• poor construction
→ the full moon should be mentioned before "even if the moon isn't directly shining."
Without mention of the full moon first, "even if the moon isn't directly shining . . ." butts into the sentence out of nowhere.

→ the phrase in the days close to the full moon is poorly placed at the end of the sentence
The study is not about sleep patterns generally but rather about sleep patterns in the days close to a full moon.
The phrase in the days close to a full moon should precede the findings.
ELIMINATE A


• I do not see any errors
• meaning is clear: three parallel verb phrases describe how a full moon affects human sleeping patterns
KEEP


To maintain parallel structure, we need either
(1) the word and to be placed before the word sleep [list structure: A, and B1 and B2]
or
(2) the word sleep to be repeated before for a shorter duration AND a comma to be placed after "deeply."
GMAC does not play: the Oxford comma is a thing.
Lists of more than two items, or two items in which the second is itself compound, require COMMA + AND before the last item on the list.
Speakers of British English, be a bit careful. The Oxford comma is rarely used in B.E.
The Oxford comma is almost never used in print journalism in order to save space.

Correct: people take longer to doze off, and sleep less deeply and for a shorter duration . . . [in this rendition, we have one "singular" list item and one "compound" list item,
Correct: people take longer to doze off, sleep less deeply, and sleep for a shorter duration . . . [in this rendition, we have three "singular" list items]

→ as in option A, the phrase in the days close to the full moon is poorly placed at the end of the sentence
The study is not about sleep patterns generally but rather about sleep patterns in the days close to a full moon.
The phrase in the days close to a full moon should precede the findings.

ELIMINATE C


• the word sleep should be repeated so that the third element in the list is parallel to the two others (see analysis of option B)
Otherwise, we have
A study has found that
. . . people take longer to doze off
. . . people sleep less deeply, AND
. . . people for a shorter duration

ELIMINATE D

[/quote]
• sleeping less deeply creates silly meaning
→ sleeping less deeply is a modifier of the previous clause, but that setup makes no sense.
How can a person sleep lightly or deeply if she is not yet asleep, i.e., how can she be sleeping less deeply if she is awake (and taking a long time to doze off)?
→ sleeping less deeply cannot be a modifier that provides more explanation of the previous part
ELIMINATE E

The best answer is B.

COMMENTS

Well, this group is a nice blend of veterans and newcomers—it's good to see you all.

Answers with explanations get kudos.
Stay safe, everyone.