The commands in this section all have essentially the same form. Their input is a standard basis, together with a list of ring variables. This variable list informs Macaulay that these are the actual variables: the other variables are to be treated as if they were in the ground field.
This is mainly useful when the monomial order of the base ring R of the standard basis is a product order. Suppose that
is a polynomial ring. Let ;SPMgt; be the product order 
. The ``t'' variables are to be ``considered as
constants''. If 
is a polynomial, then we can write
Notice that in the product order each monomial of 
is
ordered greater than every other monomial of f.
The commands in this section refer to the following notation. Let the
variables in the variable list be called the ``x'' variables, and the other
variables the ``t'' variables. Let 
be a standard basis for
the ideal or submodule I. We can always write this standard basis as:
where each monomial of 
in 
occurs before each
monomial of not shown.
The default variable list, if one is not given, is always the first block of variables. Caveat: the default is not the set of all the variables.