FILE
	/usr/common/sys/sould.c

NAME
	is_valid - returns whether a verb is a known social

PROTOTYPE
	int is_valid(string verb)

CALLED BY
	System, Common, Game

DESCRIPTION
	Checks whether the supplied verb is a valid social, and returns
	true or false.

RETURN VALUE
	1 if the verb is valid, 0 if it isn't, -1 if the query isn't allowed

ERRORS
	Normally none.

SEE ALSO
	all_socials