Under today's mendical condition, it's hard to call a 65-year old person an old man. Most of them are still strong and energetic enough to do everything. In fact, though people of age 65 have retired in my country, there still need to take care of their grandchildren. In that case, they always need to answer all the questions the kids ask them, and most of which are related to technology, science and other new things. They have to learn something new about these themes. Their ways of getting new informations are limit. Books, newspapers and maganizes , these traditional ways have slowly been out of date. A variety of apps provide a bulk of informations for people to learn. These information changes every second. Children can learn them without teachers and adults which also forces adults to learn more things besides their work. If we don't, children and adults will seem like two groups who live in two different worlds. How will the world work in the future? The people who spend time with the children most are the people above 65. So, what's your choice if you are aperson above 65?