To mislay something is to put it down somewhere and then be unable to remember where. The thing is not gone from the world — it is almost certainly in your house, in your bag, on some shelf — it is just that you and it are temporarily out of contact. That hope is built into the word. If you say you have mislaid your passport, you are saying you expect it to turn up.

To mislay somethingmislay一件東西 is是 to put it down somewhere把它放到某個地方 and then然後 be unable to remember where想不起來放在哪. The thing東西 is not gone from the world沒有從世界上消失 — it is almost certainly幾乎一定 in your house在你家, in your bag你的包包裡, on some shelf某個架子上 — it is just that只是 you and it你跟它 are temporarily out of contact暫時失去聯絡. That hope這種「還會找到」的期待 is built into the word就藏在這個字裡. If you say如果你說 you have mislaid your passport你mislaid了護照, you are saying意思是 you expect it to turn up你認為它會再出現.

It is used about small, portable things you handle every day: keys, glasses, a phone, a form, a receipt, someone's letter. You would not mislay a car or a person.

It is used這個字用在 about small, portable things小小的、可以帶著走的東西上 you handle every day你每天在用的: keys鑰匙, glasses眼鏡, a phone手機, a form表格, a receipt收據, someone's letter別人的信. You would not mislay你不會mislay a car or a person一台車或一個人.

The form to watch is the past: mislay, mislaid, mislaid — like lay, laid, laid. Never "mislayed".

The form to watch要注意的是 is是 the past過去式的變化: mislay, mislaid, mislaidmislay、mislaid、mislaid — like就像 lay, laid, laidlay、laid、laid一樣. Never絕對不是 "mislayed"「mislayed」.

Now, the honest part. This word is more British than American, and even in Britain it has an old-fashioned, careful feeling to it. Younger speakers mostly just say lost, or "I can't find my keys".

Now, the honest part現在，講老實話的部分. This word這個字 is more British than American比較英式，不太美式, and even in Britain就連在英國 it has an old-fashioned, careful feeling to it也帶著一種過時、講究的感覺. Younger speakers年輕人 mostly just say大多只會說 lostlost, or "I can't find my keys"或是「我找不到鑰匙了」.

You will meet mislay in books, in polite notices, and in the speech of older or more formal people — a hospital saying "if you have mislaid your appointment card", say, where lost would sound like an accusation. Knowing the word is genuinely useful for reading; using it in casual conversation with your friends would sound a bit bookish, and that is fine to know in advance.

You will meet mislay你會遇到mislay in books在書裡, in polite notices禮貌的告示裡, and還有 in the speech of older or more formal people年紀較大或比較正式的人的話裡 — a hospital saying比如醫院會說 "if you have mislaid your appointment card"「如果你mislaid了預約卡」, say用, where lost would sound like an accusation用lost反而聽起來像在指控人. Knowing the word知道這個字 is genuinely useful for reading對閱讀真的有用; using it in casual conversation但如果在跟朋友輕鬆聊天時用它 with your friends, would sound a bit bookish會聽起來有點書卷氣, and that is fine to know in advance先知道這點也不錯.