In a scenario like this, I don't suppose it is bad form to just flip a coin. Heads or tails?

　　I'll do the body in the acid, okay?

　　Heads or tails?

　　Heads.

　　Best two out of three?

　　知识点笔记：

　　Flip a coin 扔硬币

　　Let's flip a coin. 我们来扔硬币吧。

　　【例句一】

　　Let's flip a coin and if you win we'll go with your idea.

　　我们来扔硬币吧，如果你赢了就用你的主意。

　　【例句二】

　　Since we can't decide, let's just flip a coin to see what to do.

　　既然我们没法决定，那我们就扔硬币来决定怎么做吧。

　　Heads or tails? 正面还是反面？

　　【例句一】

　　What do you want? Heads or tails?

　　你要什么？正面还是反面？

　　【例句二】

　　Heads or tails. You choose.

　　正面还是反面？你选吧。

　　Best two out of three? 三局两胜？

　　【例句一】

　　You got lucky. Best two out of three?

　　你好幸运，咱们三局两胜？

　　【例句二】

　　Before we start, let's agree best two out of three wins.

　　开始之前说好，我们三局两胜。

　　Call it. 你来选

　　【例句一】

　　Heads or tails. Call it.

　　正面还是反面，你选。

　　【例句二】

　　I'll flip it. You call it.

　　我来扔，你来选。

　　Coin toss

　　（体育比赛中）扔硬币（决定场地）

　　【例句】

　　They lost the coin toss so their playing against the wind in the first half.

　　扔硬币他们输了，所以第一句他们要逆风比赛了。

　　Coin toss 赢面各一半

　　简单表达：

　　It's a coin toss.

　　赢面各一半。（尤其指最后一局比赛）

　　【例句一】

　　I really don't know who will win. It's a coin toss.

　　我也不知道谁会赢，胜负率各一半吧。

　　【例句二】

　　They're both great proposals so I don't know, which one the boss will choose. It's a coin toss.

　　它们都是非常好的提案，我也不知道老板会选哪一个，胜负率各一半吧。