I found this (object) outside, I think someone must have dropped it.
You can simply say, 'I think someone dropped this' when passing or showing an object you have found. If you require more details, you can say you found this outside and that you think someone might have dropped it. You can also say "I think someone lost their (object)". Dropped and lost are both considered accidents.
シンプルに、"I think someone dropped this" と言うことができます。見つけた物を誰かに渡したり、見せたりする時に使います。
もっと詳しく伝えるなら、例えば：
"I found this outside"
「外で見つけました」
"I think someone must have dropped it"
「誰かが落としたんじゃないか」
また、"I think someone lost their (object)" という言い方できます。"dropped" も "lost" も「誤って落とした」というニュアンスです。
I came across a wallet, lying on the ground, I think its been dropped by a customer
When we find things...we are said to have " come across" them...
"I found it" : equates to..." I came across it..." IE "I came across" an article on diet...
"I came across" a really great pub...way out, in the country.
I came across a bag/wallet/..it was lying in the street
何かを見つけたとき、"come across"という表現を使います。
"I found it"は" I came across it..." と同じ意味として使われます。
例文
I came across an article on diet.
ダイエットに関する記事を見つけた。
I came across a really great pub in the country.
その国で、すごくいいパブを見つけた。
I came across a bag/wallet/..it was lying in the street.
かばん/財布を見つけた。それは道に落ちていた。
I found this wallet on the floor outside, someone must have dropped it.
Someone must have dropped this wallet which I found on the floor outside.
Luckily enough, people do not carry a lot of cash in their wallets these days. Purchases are normally done by card. This is because carrying cash in one's wallet poses some risks. Firstly, one can be pick-pocketed and lose all the money in the wallet, secondly, one can be attacked and get robbed.
So, you may report this and say:
I found this wallet on the floor outside, someone must have dropped it.
or
Someone must have dropped this wallet which I found on the floor outside.
幸い、この頃は財布に現金をあまり入れていない人が多いですね。
カードでの買い物が普通です。
これは財布にたくさんお金を入れておくと危ないからですね。
万引に遭えば財布のお金を全部取られてしまいますし、強盗もあります。
こんな時には下記のように言えます：
I found this wallet on the floor outside, someone must have dropped it.
〔訳〕外の床に財布が落ちてました、きっと誰かが落としたんじゃないかな。
もしくは、
Someone must have dropped this wallet which I found on the floor outside.
〔訳〕この財布誰かが落としたんじゃないかな。外の床に落ちてました。
I picked up this wallet outside. I think someone must have lost it.
This is what a typical person in London would sound like whilst living in London. They would state what they have done and then their opinion of what they thought has happened.
In English allot of things are implied. This means it is not always said directly.
TO MISLAY something means that you have lost something - hopefully temporarily. Even if people have lost something permanently, they may use the verb 'to mislay' as it does not make them appear so stupid!
Eg. 'John told all his friends he had mislaid his wallet, but actually, he dropped it into the sea while fishing.'
MISLAY something' は「（願わくば一時的に）～を紛失する」という意味です。
仮に永続的に何かをなくしたとしても、'to mislay' が使われることがあります。そこまで間抜けに見えないからです！
例：
'John told all his friends he had mislaid his wallet, but actually, he dropped it into the sea while fishing.'
（ジョンは友達みんなに財布をどこかに置き忘れてしまったと説明したけど実際は釣りをしていたときに海の中に落としたんだ）
Hey guys, I found this outside, someone probably dropped it.
Someone probably dropped this. I found it in the supermarket.
Native speakers will say like this: “Hey guys, I found this outside, someone probably dropped it.”.
There are lots of other ways to say it, but this one is the most accurate and most commonly used.
Here is an example on how to use this in a conversation:
A: Hey guys, I found this outside, someone probably dropped it.
B: Oh, where did you find it?
A: In the supermarket.
B: Leave it in the "Lost and Found box", someone will probably come to get it.
A: Ok, thanks!
ネイティブスピーカーは次のように言います。
“Hey guys, I found this outside, someone probably dropped it.”
（ねぇ、外でこれ見つけた。たぶん誰かが落としたんだと思う）
他にもいろいろな言い方ができますが、これが最も正確で一般的です。
会話では以下のように使えます。
A: Hey guys, I found this outside, someone probably dropped it.
B: Oh, where did you find it?
A: In the supermarket.
B: Leave it in the "Lost and Found box", someone will probably come to get it.
A: Ok, thanks!
↓
A: ねぇ、外でこれ見つけた。たぶん誰かが落としたんだと思う。
B: どこで見つけたの。
A: スーパーだよ。
B: 落とし物箱に入れておきなよ。たぶん誰か取りに来るよ。
A: 分かった、そうする。ありがとう。
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