Grammatically Correct: The writer's essential guide to punctuation ...

PUNCTUATION
This sentence is fine if what's meant is legislation that applies to
all drivers. However, what if it is legislation pertaining only to people
who have just received their licenses? In that case, the sentence
should appear as: The new-driver legislation will take effect next
month.
Similarly,
Ten month old babies were observed in the study.
Did the study look at ten babies, each of whom was one month
old-or at an unspecified number of babies, each of whom was ten
months old? In the absence of hyphens, we can't tell whether ten
is modifying babies or months. This sentence should read either
Ten month-old babies were observed in the study or Ten-monthold
babies were observed in the study.
In other cases, the absence of a hyphen might not render a
sentence ambiguous, but could cause momentary confusion as the
reader started to process things one way and then realized that a
word was misinterpreted.
The company sponsored events usually attracted a high turnout.
The office generated paperwork soon became too much for one
secretary to handle.
His girlfriend related problems began to take their toll on his work.
Hyphens would make it clear that sponsored, generated and
related are functioning as parts of compound adjectives, not as
verbs.
Exceptions
Hyphens may be considered optional when a compound adjective
consists of words that are quite commonly associated with each
other, so there is little possibility of ambiguity or misinterpretation.
The earlier examples of major league player and mad cow disease
could quite properly be written as major-league player and madcow
disease. However, this is more a choice than a necessity, since
omitting the hyphens should not cause any problems for the reader.
In some cases, adding hyphens would be not only unnecessary
but inappropriate. For example, you would not include them in
phrases such as high school student, baby boomer generation or
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