(每日一词）unison

unison /ˈjuː.nə.sən/ n. 齐唱，齐奏

meaning: the playing or singing of notes at the same pitch by different instruments or voices 

1) 前缀：uni- 单，一

2) 词根：son- 声音（sound) 

3) 后缀：-ion 名词后缀

e.g. “We want’ ice cream!” The children chanted in unison. “我们要吃冰激凌！”孩子们齐声不断喊道。