* @param teacher an <code>Unit</code> value
     */
    public void assignTeacher(Unit student, Unit teacher) {
        Player player = freeColClient.getMyPlayer();
        if (!requireOurTurn()
            || student == null
            || !player.owns(student)
            || student.getColony() == null
            || !(student.getLocation() instanceof WorkLocation)
            || teacher == null
            || !player.owns(teacher)
            || !student.canBeStudent(teacher)
            || teacher.getColony() == null
            || student.getColony() != teacher.getColony()
            || !teacher.getColony().canTrain(teacher)) {
            return;
        }

        askServer().assignTeacher(student, teacher);
    }