Note to the student 中文翻譯

（Coming from the Preface of Quantum Mechanics written by Nouredine Zettili）

No one expects to learn swimming without getting wet. Nor does anyone expect to learn it by merely reading books or by watching others swim. Swimming cannot be learned without practice. There is absolutely no substitute for throwing yourself into water and training for weeks, or even months, till the exercise becomes a smooth reflex.

Similarly, physics cannot be learned passively. Without tackling various challenging problems, the student has no other way of testing the quality of his or her understanding of the subject. Here is where the student gains the sense of satisfaction and involvement produced by a genuine understanding of the underlying principles. The ability to solve problems is the best proof of mastering the subject. As in swimming, the more you solve problem, the more you sharpen and fine-tune your problem-solving skills.

To derive full benefit from the examples and problems solved in the text, avoid consulting too early the solution. If you cannot solve the problem after you first attempts, try again! If you look up the solution after several attempts, it will remain etched in you mind for a long time. But if you manage to solve the problem on your own, you should still compare your solution with the book's solution. You might find a shorter or more elegant approach.

給學生的話 英文原文

（Coming from the Preface of Quantum Mechanics written by Nouredine Zettili）

沒有人可以不碰水就學會游泳。也沒有人認為光靠讀書或看其他人游泳就學得會。沒有練習是沒法學會游泳的。除了把你丟進水裡，訓練上好幾個星期，或甚至幾個月，直到反應純熟之外，絕對沒有其他替代的辦法。

類似地，被動的方式是學不到物理的。如果沒有克服過各類難題，學生沒辦法測知他或她對這個科目了解的程度。藉著這種對基礎原理貨真價實的了解，學習者才會有參與感及滿足感。對一個科目熟不熟練，最好的證明就是解決問題的能力。就像游泳一樣，你解的問題越多，你就越可以改善及增進解題能力。

要從課本的例題與習題裡得到最大的好處，就不要急著看解答。如果你試了一下解不出來，再試一次！試了很多次之後再看解答的話，它會長久地烙印在你的腦子裡。如果你想辦法靠自己的力量解出了問題，你仍然可以和課本的解答比較。因為你可能會發現更快或更優美的解法。