how do you undersdand "once the sands have run out of a person's hourglass,

问题描述:

how do you undersdand "once the sands have run out of a person's hourglass,
how do you undersdand "once the sands have run out of a person's hourglass,they cannot be replaced"

It means that time is running and it'll never come back.Just like the old saying goes:Time and tide wait for no man.