běn / lái / zhǐ / shì / kāi / wán / xiào / méi / xiǎng / dào / nòng / jiǎ / chéng / zhēn / liǎng / gè / rén / zhēn / de / chǎo / qǐ / lái / le

本来只是开玩笑，没想到弄假成真，两个人真的吵起来了。

It was just a joke at first, but it turned real; the two people actually started arguing.