(defrule GetGender
(declare (salience 100))
(printout t "What's your gender ? (Male/Female): ")
(bind ?response (read))
(assert (Gender (gender ?response))))

(defrule GetShirt
(declare (salience 99))
(Gender (gender ?l))
(test (= ?l Male))
=>
(printout t "What's your shirt color ? (Blue/Black): ")
(bind ?response (read))
(assert (Shirt (shirt ?response))))