She visited Paris once.
她曾经去过巴黎。
I met him once at a party.
我曾经在一个聚会上见过他。
We went there once last year.
我们曾经去年去过那里。
He called me once yesterday.
他曾经昨天给我打过电话。
She once lived in New York.
她曾经住在纽约。
They once owned a restaurant.
他们曾经拥有一家餐馆。
I once saw a UFO.
我曾经见过一个不明飞行物。
We once traveled to Japan.
我们曾经去过日本旅行。
He once climbed Mount Everest.
他曾经攀登过珠穆朗玛峰。
She once worked as a teacher.
她曾经当过老师。
once upon a time
(用于故事的开头)从前, 很久以前
all at once
突然, 忽然；一起, 同时
once again
又一次, 再一次
at once
立即, 马上
once in a while
偶尔
