确信无疑，放心

1. 放心：Flex不仅有专家能手们的坚实市场基础,并且产品本身也变得更加健壮(robust)和开放,现在开发者们可以明智地增加Flex作为技术组合之一,并且大可放心(rest assured),他们绝对选择了一项伟大的技术!

2. 绝对放心：It could change your life|它可以改变你的生活 | Rest assured|绝对放心 | And it's my job|也是我的工作

3. 请放心：...l'm sick and know what l have to do.|...我病了 我知道我该做些什么 | Rest assured...|请放心... | ...I shall always...|...我会始终...

4. 安枕无忧：安如泰山 as firm as a rock | 安枕无忧 rest assured | 按兵不动 bide one's time

2. rest assured的解释