被試的是人
核心畫面裡站在場上的是一個人，看的人要從中挑出幾個。
noun · B2
An event at which people who want a place on a sports team, in a group, or in a show are tested, so that the people in charge can choose the best ones. It is often used in the plural, as tryouts.
選拔；試訓
核心畫面
One picture covers the word: a short, real run before the real thing, watched by someone who has still to decide. Nothing here is final. Somebody performs or something is used, somebody watches and takes notes, and afterwards a yes or a no is given. Change who is being watched and the word moves from a gym to an office to a theatre, but the shape of the event never changes.
這個字可以想成一個場面：正式來之前，先真的做一次給人看，而看的人還沒決定。這裡面沒有任何事情是定案的。有人上場表現，…更多收起
這個字可以想成一個場面：正式來之前，先真的做一次給人看，而看的人還沒決定。這裡面沒有任何事情是定案的。有人上場表現，或是有東西被拿來用，旁邊有人看著、記著，結束後才給出要或不要。把「被看的對象」換掉，場景就從球場換到辦公室、再換到劇場，但事情的形狀完全沒變。From the word’s history
The noun comes straight from the phrasal verb try out. Freezing the phrase into a noun turns the action of trying something into the occasion on which it is tried.
這個名詞是直接從片語動詞 try out 來的。把片語凍成一個名詞，原本的動作「試試看」就變成「試的那一次、那一段時間」。
Wiktionary entry for tryout, supplied in this evidence packet (kaikki:3f6f69a190036ae4:1472905223): Deverbal from try out.
Two branches
被試的是東西
同一個場面，只是站上去被看的不是人，而是一個東西或一齣戲。
noun · B2
An occasion when something new is used or tested for a while, so that people can see how well it works before they decide whether to keep it.
試用；試行
原始詞典資料1 筆記錄
以下是外部詞典記錄的用法，原文照列，我們還沒有寫成教學內容。上面的說明才是我們自己寫的；有些用法可能上面已經講過了。
tryoutnoun/ˈtɹaɪˌaʊt/
- 1
A test of the suitability or effectiveness of a person or thing, especially an audition for a performer or athlete, or the advance staging of a play at a small theatre.
- “Hey, what are you guys doing?” “Dude, we're gonna tailgate the tryouts.” “Oh, shit. That's a good idea. Oh, you gonna bust out Green Man, bro?” “No. No Green Man.” “What's Green Man?” “Well, in high school, Charlie was like our school mascot.” “A mascot nobody wanted. He'd get wasted and dress in this green spandex bodysuit.” “Spandex?” “It was really sad.” “That's it.” “You gotta bring the Green Man suit.” “Yeah, no. Done with it.” “The spandex.” “Green Man was good. It got me through some hard times. But I'm done with it. Tell you what. You can wear it if you want, but I'm just gonna be relaxing, okay? This is gonna be about chilling out for me.” “No. This is gonna be exactly like Woodstock.”
- Oh, there's only one spot open right now, so we're gonna have tryouts.
資料來源：英文維基詞典 English Wiktionary（CC BY-SA 4.0）。 原文照列，未經改寫。