Subject and verb agreement

many rules exists in the topic of subject and verb agreement

my summary:
* uncountable noun should be followed by singular form, unless "a large sums of" or "quantities of"
* plural countable noun should always be followed by plural verb.

* singular:
* one of
* -ing, to be, as subject
* a and b (a and b refer to the same thing)
* either(neither) of
* another, each one, no one, neither, the other, each, each of, either, everything, anything, something
* no
* specified noun
* time, distance, measurement

* plural:
* two of
* a and b, both a and b
* half(rest, plenty, part, fifty percent) of
* both(few, many, several) of
* all(none, most, any) of

* no effect modifiers
* along with, as well as, accompanied by, besides, combined with, in addition to, including, rather than, no less than, together with, with, for example
* form, type, kind of

* closest agreement
* there be
* reverse ordered
* either ... or, neither ... nor, not only ... but (also), nor, or
* one of xx that

* non-countable
* a amount of
* quantity of
* much
* little

* countable
* a number of
* many
* few

* special
* The students each have a book

my tips:
* check the answers at first to identify the grammar point that ETS is checking.
* it is sometimes not hard to see that the point is about subject and verb agreement.