这两盏灯交替闪烁，营造出节日气氛。

The two lights ___alternated flickering, creating a festive atmosphere.

我们轮流照顾婴儿，这样每个人都能得到休息。

We ___alternated caring for the baby so everyone could get some rest.

老师在课堂上交替使用英语和中文进行讲解。

The teacher ___alternated between English and Chinese during the lecture.