foolproof
adj
1 not capable of going wrong or of being misunderstood; very plain and simple 不会错的; 不会引起误解的; 非常简单明了的
a foolproof method, plan, scheme, etc 万无一失的方法、 计画、 方案等.
2 not capable of going wrong or of being used wrongly; reliable and easy to operate 不会做错的; 不会用错的; 可靠而操作简便的
a foolproof security system 可靠的安全系统.