It is used to fill out one or more fields in this item using tag if it finds a matching rule expansion. It uses weight as an attribute to indicate the probability or the weightage of an element being associated with a rule expansion.



It indicates that this rule reference points to a built-in rule. It can be #GARBAGE, # NULL or #VOID.


It indicates that the contents of the specified item may be repeated. Possible patterns are:

0-1 Optional.

0- Can occur zero or more times.

1- Can occur one or more times.

n- Can occur n or more times.

n-m Can occur between n and m times.


The expected probability of this item’s rule expansion being spoken.


The language used with the element. (E.g.) en-US for US English.


Item, one-of, rule


count, item, one-of, ruleref, tag and token