But we don't always feel sure of that.

然而我们不是时常都感受到这个确据。

It seems to me there must be something outside, and I feel sure of it.

我似乎觉得外面发生了一些事情——我有这种预感！

Use some type of rapid prototyping whenever possible to help customers feel sure of their requirements and minimize changes.

使用一些快速原型的开发方法可以帮助客户确认需求，减少后期的改变。

You may feel all the training a waste of time, but I'm a hundred percent sure later you'll be grateful you did it.

你可能觉得所有的训练都是在浪费时间，但我百分之百地肯定，以后你会庆幸你做过这一切。

You may feel all the training a waste of time, but I'm a hundred percent sure later you'll be grateful for what you did.

你可能觉得所有的训练都是浪费时间，但是我百分之百确定你以后会感激你所做的一切。