①There is a widespread humorous saying that ______（引入格言）. Funny as it is, the saying ironically reflects the fact that ______（名言所反映的事实）.

②Our life involves all kinds of obstacles and setbacks which may exhaust us. Therefore, ______ （中心论点）. What's more, ______（进一步阐述中心论点）. For example, ______（举例论证）. Obviously, ______（好出本段结论）.

③All in all, ______（结论）, just as the old popular saying goes, ______（呼应开头）.