Life has its ebbs and flows.
人生有起有落。
该句使用简单现在时结构表达普遍真理。
"In life, there are wins and losses, hopes and setbacks."
"Life swings like a pendulum between pain and boredom."
"Life inevitably brings unpredictable gains and losses, joys and sorrows."
"Life is always full of ups and downs, fluctuating through the changing years."
"Life is like a roller coaster, with its peaks and valleys"