Warm-up: a short practice or a series of gentle exercises that you do to prepare yourself for doing a particular sport or activity (体育运动等前的)适应性活动,准备活动;热身练习
He swam ten lengths of the pool as a warm-up. 他在游泳池里游了五个来回作为热身活动.
warm-up exercises 热身练习

admission: the amount of money that you pay to go into a building or to an event 入场费;门票费
admission charges/prices 入场费／票价
£5 admission 入场费 5 英镑
What's the admission? 门票多少钱?

Alternate: to make things or people follow one after the other in a repeated pattern 使交替;使轮流
Alternate cubes of meat and slices of red pepper. 交替放置肉丁和红辣椒片.
Alternate cubes of meat with slices of red pepper. 交替放置肉丁和红辣椒片.

Idle: to spend time doing nothing important 混时间;闲荡;无所事事
They idled the days away, talking and watching television. 他们天天在闲聊和看电视中消磨时光.
They idled along by the river(= walked slowly and with no particular purpose). 他们沿着河边闲逛.

Unfit: not capable of doing something, for example because of illness (因病等)不能做某事,不宜做事
He's still unfit for work. 他还不宜工作.
The company's doctor found that she was unfit to carry out her normal work. 公司的医生认为,她不宜从事正常工作.

pass something↔up: to choose not to make use of a chance, an opportunity, etc. 放弃,不要(机会)
Imagine passing up an offer like that! 真想不到居然放弃人家提供的大好机会!