said or done without having been planned or written in advance.
说话做事没有事先计划或预先写好的。
The act or right of occupying a place beforehand or in advance.
先占权事先或预先占据某地的行为或权利
Give sb anadvance warning or hint
事先给某人警告或暗示
prior informed consent procedure
事先知情的同意程序
Don't tell her about this yet.
这事先慢点告诉他。
forewarn a person of the danger
事先警告某人有危险
He arrived unannounced.
他未事先通知而来到.
amputation is the price to pay for inadequate preparation
因为他们事先准备不足
You' d better plan ahead.
你最好事先计划一下。
If you always prepare some topics before-hand,
如果你总是事先准备，
according to previous appointment.
他们要按照事先的约定。
She made an advance payment for her new car.
她事先预付了她的新车。
break with precedent,ie not act according to precedents
打破先例（不按先例行事）.
A preceding occurrence, cause, or event.
先前的前面的事件，事情
Something afforded or deserving prior attention.
优先考虑的事或值得优先注意的事
You must do it beyond all things.
你首先必须做这件事。
"What ails you, baron?"
“出什么事了，男爵先生？”
Mr. Lu goes to one of the tellers' windows at the bank.
陆先生到一个办事窗口。