At first I thought there was no one in the room.
起初我以為房裡沒有人。
"Who was that on the phone?" "No one you would know."
「誰來的電話？」「你不認識的人。」
I'd like to go to the concert but no one else (= no other person) wants to.
我想去聽音樂會，但其他人都不願意去。
No one told me she was ill.
沒人告訴我她病了。
