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

PUNCTUATION
USE SEMICOLONS IF COMMAS MIGHT CAUSE A SENTENCE
TO BE MISREAD OR OTHERWISE DIFFICULT TO FOLLOW
Even when elements are not subdivided, commas sometimes would
not suffice to mark the divisions between them. For example, what
if you came across a description like the following in some assembly
instructions:
Part A attaches to B, C and D attach toE, and F attaches to G.
It would be very easy to mistake B, C and D for a series; that is,
to start reading the sentence as Part A attaches to B, C and D.
The rest of the sentence then falls apart: . . . attach to E, and F
attaches to G (??). A second pass would probably set you straight,
but no sentence should have to be read twice to be clear. Semicolons
would prevent any confusion, ensuring that each clause is kept
distinct from the others.
Part A attaches to B; C and D attach toE; and F attaches to G.
RECOMMENDATION: IF YOU FEEL A COMMA WOULD NOT
BE STRONG ENOUGH, USE A SEMICOLON INSTEAD
EVEN IF IT IS NOT TECHNICALLY REQUIRED
Normally, independent clauses linked by a conjunction are separated
with a comma. However, if an independent clause contains any
internal commas, you may sometimes choose to use a semicolon as
the separator instead. As with a series that contains subelements,
the purpose is to make it immediately clear to the reader where one
main element ends and the next begins. For example:
It is often useful to discuss your research ideas with others before you
begin to write, as the questions that arise from the discussion may help
clarify things in your own mind. Your consultants may be experts in
your field, or they may know nothing of its methods and assumptions;
they may be familiar with your particular research project, or they may
be completely unacquainted with it; and they may be seasoned
investigators or just starting out their own careers.
Similarly, at times you may decide to use a semicolon simply
because the elements in a series are long. Given that commas perform
so many functions, it may not always be immediately apparent what
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