(每日一词）momentum

Momentum /məʊˈmɛntəm/ n. 势头, 动量

Physics meaning:(动量): The force or strength that something has when it is moving, based on its mass and speed.

Everyday meaning:(势头): The driving force or energy that keeps something growing, developing, or moving forward.

1) 词根: mo- 表示move 移动

2) 后缀: -ment 名词后缀, -um 名词后缀

例句: 

The conversation lost momentum after a while. 聊天聊到后来就没啥劲了。

I was working out every day, but then I got sick and lost my momentum. 我之前每天锻炼，但后来生病打断了，就没动力了。