Definition
This phrase is used when flipping a coin to ask someone to guess whether the coin will land heads up or tails up.
正反面？
We'll flip a coin to decide who goes first, heads or tails?
我们来掷硬币决定谁先开始，正面还是反面？
Before making this decision, why don't we flip a coin? Heads or tails?
在做这个决定之前，我们为什么不掷硬币呢？正面还是反面？
They're using a coin flip to decide what to have for dinner, I bet they will ask: heads or tails?
他们用掷硬币来决定晚餐吃什么，我打赌他们会问：正面还是反面？