Suitable Language  Types of Delivery  5-12  Figure 5-9.  Notes allow the accurate dissemination of complicated information.  Notes used wisely can ensure accuracy, jog the memory, and dispel the fear of forgetting. They are essential for  reporting  complicated information, and they may help keep the lecture on track. The instructor who requires notes should use them sparingly  and unobtrusively but at the same time should make no effort to hide them from the learners.  [Figure 5-9]  If the instructor realizes from puzzled expressions that a number of learners fail to grasp an idea, that point can be further elaborated  until the reactions indicate they understand. The extemporaneous presentation reflects the instructor’s personal enthusiasm and is  more flexible than other methods. For these reasons, it is likely to hold the interest of the learners.  A good teaching lecture utilizes an extemporaneous technique. The instructor speaks from a mental or written outline, but does not  read or memorize the material to be presented. Because the exact words to express an idea are spontaneous, the lecture is more  personalized than one that is read or spoken from memory.  Another way the instructor can add life to the lecture is to vary his or her tone of voice and pace of speaking. In addition, using  sentences of different length helps, since consistent use of short sentences results in a choppy style. On the other hand, poorly  constructed long sentences are difficult to follow and can easily become tangled. To ensure clarity and variety, the instructor should  normally use sentences of short and medium length.  If the subject matter includes technical terms, the instructor should clearly define each one so that no learner is in doubt about its  meaning. Whenever possible, the instructor should use specific rather than general words. For example, the specific words, “a leak in  the fuel line” tell more than the general term “discrepancy.”$_{ }$ In the teaching lecture, simple rather than complex words should be used whenever possible. The instructor should not, use  substandard English or errors in grammar. 