This recipe is foolproof ─ it works every time.
这个食谱绝对管用，每次都万无一失。
The system is not 100 per cent foolproof
这个系统并非是万无一失。
I spent the day working out a foolproof plan to save him.
我花了一天的时间想出了一个营救他的周全方案。
Always ensure you have a foolproof way to get paid.
永远确保你拿得到钱。
This new system is supposed to be foolproof.
据说这个新系统不会出毛病。