周末我们组织了一个轻松的唱歌活动，大家都很享受。

We organized a casual ___sing-along last weekend and everyone enjoyed it.

孩子们围在篝火旁，跟着屏幕上的歌词一起唱起了那首熟悉的合唱歌曲。

The children gathered around the campfire and sang the familiar ___sing-along with lyrics displayed on the screen.