Stress is everywhere in our everyday life. Not only men have it, but also women and young people.
   The most important reasons of stress are: death, diseases, exams, making money, getting married, moving houses, changing jobs, ending friendships and so on.
   How do you know whether you have stress or not? Could you give your answers to the following questions?

   If your answer "Yes" to more than two of these questions, you are one of those people with stress. So what can you do about it?
   Doing relaxing exercises, talking with friends and listening to light music are all usual ways of relieving (减轻) stress. However, doctors now say that there are easier ways-people should laugh and smile more often. When you laugh and smile, your body relaxes. They also say that people, especially men, should   X  more often, because crying is a natural way of relieving stress.

观察下列数据：﹣$\frac{5}{4}$，$\frac{7}{9}$，﹣$\frac{9}{16}$，$\frac{11}{25}$…它们是按一定规律排列的，依照此规律，第19个数据是____