hard and fast = fixed and sure
明确的，固定的
It is impossible to make any decisions that are hard and fast.
现在做一些明确的决定是不可能的！

one and only
唯一的
This guy is the one and the only person I love!
这个男人是我唯一爱的人！

No pain, no gain.
没有痛苦就没有收获

Grasp all, lose all.
抓住所有就失去所有
If you grasp all, you will lose all who are close to you!
如果你谁都想抓住，那你就会失去身边最重要的人！

heart and soul
倾注全力
If you put enough heart and soul into something, you will succeed for sure!
你倾注你的全力在某一件事情上，你一定会成功！

by fair means or foul
不择手段

forgive and forget
既往不咎
Would they forgive and forget？
他们会既往不咎吗？