A、The difference between a job description and a job specification. B、The difference between what is taught and how it is used.

As we know, it is very important that a firm should pay attention to the training of its staff, as there exist many weak points in its various departments.
    Staff training must have a purpose, which is defined when a firm considers its training needs, which are in turn based on job descriptions and job specifications. A job description should give details of the performance that is required for a particular job and[29]a job specification should give information about the behavior, knowledge and skills that are expected of an employee who works in it. When all of this has been collected, it is possible to make a training specification. This specified what the training department must teach for the successful performance of the job, and also the best methods to use in the training period. There are many different training methods, and there are advantages and disadvantages of all of them.[30]Successful training performance depends on an understanding of the difference between learning about skills and training in using them. It is frequently said that learning about skills takes place "off the job" in the classroom, but training in using these skills takes place "on the job", by means of such activities as practice in the workshop. It’s always difficult to evaluate the costs of a training program. The success of such a program depends not only on the methods used but also on the quality of the staff who do the training. The evaluation of management mining is much more complex than that.
29. What information does a job specification should present, according to the passage?
30. What must we understand in order to achieve a successful training performance?
31. What does the success of a training program lie in according to the passage?