Before revision: In theory, any sign could be comprised of figurae, but care must be taken in distinguishing between the control-number-like function of figurae (as in the individual digits of a telephone extension) and the syntax-like function of meaning constituents (as in the area code of a full telephone number).
After revision: In theory, any sign could be composed of figurae, but care must be taken in distinguishing between the control-number-like function of figurae (as in the individual digits of a telephone extension) and the syntax-like function of meaning constituents (as in the area code of a full telephone number).